EE testing a crystal

[Manu Abraham]

Hi,

I have the following crystal, with a frequency of 12MHz.

https://abracon.com/Resonators/ABM8G.pdf

Soldered one of these onto the desired PCB, thought of testing the
crystal using a HEF4060B by connecting between pins 9 and 10, the
crude test which has worked over the years.

Sadly there were no oscillations at all.

The next thought was to do a dead bug style, the crystal. Did that
too, but there seems to be no life at all.

As a result, thinking that the crystal could be dead, tried a brand
new exactly same ABM8G crystal in the dead bug style, which also
showed no signs of life.

Tried a 7.3728MHx crystal in it's position, that does show a clean
7.3728MHz oscillation


I am just scratching my head, lost in thoughts.

Any suggestions, anyone ?

Thanks,

Manu
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[Timmothy Relerford]

Are you exceeding the max freq operating freq of the 4060?

Regards,

Jim

> -------- Original Message --------
> Subject: EE testing a crystal
> From: Manu Abraham <***@gmail.com>
> Date: Fri, September 21, 2018 11:55 am
> To: "Microcontroller discussion list - Public." <***@mit.edu>
>
>
> Hi,
>
> I have the following crystal, with a frequency of 12MHz.
>
> https://abracon.com/Resonators/ABM8G.pdf
>
> Soldered one of these onto the desired PCB, thought of testing the
> crystal using a HEF4060B by connecting between pins 9 and 10, the
> crude test which has worked over the years.
>
> Sadly there were no oscillations at all.
>
> The next thought was to do a dead bug style, the crystal. Did that
> too, but there seems to be no life at all.
>
> As a result, thinking that the crystal could be dead, tried a brand
> new exactly same ABM8G crystal in the dead bug style, which also
> showed no signs of life.
>
> Tried a 7.3728MHx crystal in it's position, that does show a clean
> 7.3728MHz oscillation
>
>
> I am just scratching my head, lost in thoughts.
>
> Any suggestions, anyone ?
>
> Thanks,
>
> Manu
> --
> http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive
> View/change your membership options at
> http://mailman.mit.edu/mailman/listinfo/piclist

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[Manu Abraham]

Hi Jim,

Powered the setup from 14V. At 10V the datasheet does state that it
can go up to 20Mhz
and at 15V it can go up to 30Mhz.

https://assets.nexperia.com/documents/data-sheet/HEF4060B.pdf

So, I am not having a doubt on the max frequency of the 4060.

Any other thoughts ?

Thanks,

Manu


On Fri, Sep 21, 2018 at 10:46 PM, Timmothy Relerford <***@jpes.com> wrote:
>
> Are you exceeding the max freq operating freq of the 4060?
>
> Regards,
>
> Jim
>
>> -------- Original Message --------
>> Subject: EE testing a crystal
>> From: Manu Abraham <***@gmail.com>
>> Date: Fri, September 21, 2018 11:55 am
>> To: "Microcontroller discussion list - Public." <***@mit.edu>
>>
>>
>> Hi,
>>
>> I have the following crystal, with a frequency of 12MHz.
>>
>> https://abracon.com/Resonators/ABM8G.pdf
>>
>> Soldered one of these onto the desired PCB, thought of testing the
>> crystal using a HEF4060B by connecting between pins 9 and 10, the
>> crude test which has worked over the years.
>>
>> Sadly there were no oscillations at all.
>>
>> The next thought was to do a dead bug style, the crystal. Did that
>> too, but there seems to be no life at all.
>>
>> As a result, thinking that the crystal could be dead, tried a brand
>> new exactly same ABM8G crystal in the dead bug style, which also
>> showed no signs of life.
>>
>> Tried a 7.3728MHx crystal in it's position, that does show a clean
>> 7.3728MHz oscillation
>>
>>
>> I am just scratching my head, lost in thoughts.
>>
>> Any suggestions, anyone ?
>>
>> Thanks,
>>
>> Manu
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[Jean-Paul Louis]

Pin 10 and 11 are for the oscillator, not 9 and 10

Sent from Yahoo Mail on Android

On Fri, Sep 21, 2018 at 12:57 PM, Manu Abraham<***@gmail.com> wrote: Hi,

I have the following crystal, with a frequency of 12MHz.

https://abracon.com/Resonators/ABM8G.pdf

Soldered one of these onto the desired PCB, thought of testing the
crystal using a HEF4060B by connecting between pins 9 and 10, the
crude test which has worked over the years.

Sadly there were no oscillations at all.

The next thought was to do a dead bug style, the crystal. Did that
too, but there seems to be no life at all.

As a result, thinking that the crystal could be dead, tried a brand
new exactly same ABM8G crystal in the dead bug style, which also
showed no signs of life.

Tried a 7.3728MHx crystal in it's position, that does show a clean
7.3728MHz oscillation


I am just scratching my head, lost in thoughts.

Any suggestions, anyone ?

Thanks,

Manu
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[Manu Abraham]

Hi Jean-Paul,


I meant to write pins 10 and 11. It is wired with 10 & 11.
The setup works with other crystals. Just this one I'm worried.
But a newer one also just shows up with no life.

Any other thoughts ?

Thanks,

Manu


On Fri, Sep 21, 2018 at 10:52 PM, Jean-Paul Louis <***@yahoo.com> wrote:
> Pin 10 and 11 are for the oscillator, not 9 and 10
>
> Sent from Yahoo Mail on Android
>
> On Fri, Sep 21, 2018 at 12:57 PM, Manu Abraham
> <***@gmail.com> wrote:
> Hi,
>
> I have the following crystal, with a frequency of 12MHz.
>
> https://abracon.com/Resonators/ABM8G.pdf
>
> Soldered one of these onto the desired PCB, thought of testing the
> crystal using a HEF4060B by connecting between pins 9 and 10, the
> crude test which has worked over the years.
>
> Sadly there were no oscillations at all.
>
> The next thought was to do a dead bug style, the crystal. Did that
> too, but there seems to be no life at all.
>
> As a result, thinking that the crystal could be dead, tried a brand
> new exactly same ABM8G crystal in the dead bug style, which also
> showed no signs of life.
>
> Tried a 7.3728MHx crystal in it's position, that does show a clean
> 7.3728MHz oscillation
>
>
> I am just scratching my head, lost in thoughts.
>
> Any suggestions, anyone ?
>
> Thanks,
>
> Manu
> --
> http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive
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[David Van Horn]

It might be worth noting that Crystals != Resonators != Oscillators.

Resonators frequently include the capacitors they need to work. Generally looser tolerance than crystals.


Crystals generally need external capacitors to work in a parallel resonant circuit, and the correct C value is (2 * Cspec) - Cstray
Ex: for a 22pF crystal, and assuming 6pF for stray capacitance, use (2*22)-6=38pf so use 39pF.
Despite what you may read, the capacitor value is driven by the crystal spec sheet and NOT the chip data sheet!
https://www.foxonline.com/pdfs/xtaldesignnotes.pdf
If the chip data sheet calls out a capacitance, then they MAY be telling you to use a crystal designed for that load capacitance, or they may have capitulated to hordes of hobbyists demanding that they show cap values in their data sheets.
If the caps are correct, then the crystal will run at the correct frequency in circuit. If it's off more than the data sheet tolerance, then you have the wrong caps.


Oscillators take power and ground and have an output pin that gives you a signal.

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[Manu Abraham]

Hi David,

Aware of the differences between crystals, resonators, oscillators.

That said, ABM8G is a crystal, not a resonator.
"ULTRA MINIATURE CERAMIC GLASS SEALED SMD CRYSTAL"
And it has a Load capacitance CL=10pF

If you look at the outline drawing, it indeed shows a crystal and not
a resonator.

The crystal has 2 shielding pins for GND, but not for any power.
That's why it has 2 additional pins, for GND.

I believe you took it for a resonator, due to the resonators folder
embedded in the link ?

The capacitance I am using is indeed 10pF C0G
http://www.avx.com/products/ceramic-capacitors/surface-mount/c0g-np0-dielectric/


Thanks,

Manu



On Sat, Sep 22, 2018 at 12:26 AM, David Van Horn
<***@backcountryaccess.com> wrote:
> It might be worth noting that Crystals != Resonators != Oscillators.
>
> Resonators frequently include the capacitors they need to work. Generally looser tolerance than crystals.
>
>
> Crystals generally need external capacitors to work in a parallel resonant circuit, and the correct C value is (2 * Cspec) - Cstray
> Ex: for a 22pF crystal, and assuming 6pF for stray capacitance, use (2*22)-6=38pf so use 39pF.
> Despite what you may read, the capacitor value is driven by the crystal spec sheet and NOT the chip data sheet!
> https://www.foxonline.com/pdfs/xtaldesignnotes.pdf
> If the chip data sheet calls out a capacitance, then they MAY be telling you to use a crystal designed for that load capacitance, or they may have capitulated to hordes of hobbyists demanding that they show cap values in their data sheets.
> If the caps are correct, then the crystal will run at the correct frequency in circuit. If it's off more than the data sheet tolerance, then you have the wrong caps.
>
>
> Oscillators take power and ground and have an output pin that gives you a signal.
>
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[David Van Horn]

These things frequently come up, and some people don't understand the differences.
Maybe that comment will be useful when someone searches up this thread.

10pF is fun, do you know what your strays are?
The cap value then should be 20pF - Cstray = ??

10pF cap is likely a bit light, unless your strays are large.


-----Original Message-----
From: piclist-***@mit.edu <piclist-***@mit.edu> On Behalf Of Manu Abraham
Sent: Friday, September 21, 2018 1:08 PM
To: Microcontroller discussion list - Public. <***@mit.edu>
Subject: Re: EE testing a crystal

Hi David,

Aware of the differences between crystals, resonators, oscillators.

That said, ABM8G is a crystal, not a resonator.
"ULTRA MINIATURE CERAMIC GLASS SEALED SMD CRYSTAL"
And it has a Load capacitance CL=10pF

If you look at the outline drawing, it indeed shows a crystal and not a resonator.

The crystal has 2 shielding pins for GND, but not for any power.
That's why it has 2 additional pins, for GND.

I believe you took it for a resonator, due to the resonators folder embedded in the link ?

The capacitance I am using is indeed 10pF C0G http://www.avx.com/products/ceramic-capacitors/surface-mount/c0g-np0-dielectric/


Thanks,

Manu



On Sat, Sep 22, 2018 at 12:26 AM, David Van Horn <***@backcountryaccess.com> wrote:
> It might be worth noting that Crystals != Resonators != Oscillators.
>
> Resonators frequently include the capacitors they need to work. Generally looser tolerance than crystals.
>
>
> Crystals generally need external capacitors to work in a parallel
> resonant circuit, and the correct C value is (2 * Cspec) - Cstray
> Ex: for a 22pF crystal, and assuming 6pF for stray capacitance, use (2*22)-6=38pf so use 39pF.
> Despite what you may read, the capacitor value is driven by the crystal spec sheet and NOT the chip data sheet!
> https://www.foxonline.com/pdfs/xtaldesignnotes.pdf
> If the chip data sheet calls out a capacitance, then they MAY be telling you to use a crystal designed for that load capacitance, or they may have capitulated to hordes of hobbyists demanding that they show cap values in their data sheets.
> If the caps are correct, then the crystal will run at the correct frequency in circuit. If it's off more than the data sheet tolerance, then you have the wrong caps.
>
>
> Oscillators take power and ground and have an output pin that gives you a signal.
>
> --
> http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive
> View/change your membership options at
> http://mailman.mit.edu/mailman/listinfo/piclist
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[Manu Abraham]

Even more fun is the NX5032GA, It has a CL=8pF. With the 4060 it works
beautifully without any CL. I guess the stray capacitance was probably around
4pF or so. That was before soldering; It could've changed. CL, I guess
is unlikely
an issue here, even without CL, the ABM8G shows no life.

On Sat, Sep 22, 2018 at 12:53 AM, David Van Horn
<***@backcountryaccess.com> wrote:
> These things frequently come up, and some people don't understand the differences.
> Maybe that comment will be useful when someone searches up this thread.
>
> 10pF is fun, do you know what your strays are?
> The cap value then should be 20pF - Cstray = ??
>
> 10pF cap is likely a bit light, unless your strays are large.
>
>
> -----Original Message-----
> From: piclist-***@mit.edu <piclist-***@mit.edu> On Behalf Of Manu Abraham
> Sent: Friday, September 21, 2018 1:08 PM
> To: Microcontroller discussion list - Public. <***@mit.edu>
> Subject: Re: EE testing a crystal
>
> Hi David,
>
> Aware of the differences between crystals, resonators, oscillators.
>
> That said, ABM8G is a crystal, not a resonator.
> "ULTRA MINIATURE CERAMIC GLASS SEALED SMD CRYSTAL"
> And it has a Load capacitance CL=10pF
>
> If you look at the outline drawing, it indeed shows a crystal and not a resonator.
>
> The crystal has 2 shielding pins for GND, but not for any power.
> That's why it has 2 additional pins, for GND.
>
> I believe you took it for a resonator, due to the resonators folder embedded in the link ?
>
> The capacitance I am using is indeed 10pF C0G http://www.avx.com/products/ceramic-capacitors/surface-mount/c0g-np0-dielectric/
>
>
> Thanks,
>
> Manu
>
>
>
> On Sat, Sep 22, 2018 at 12:26 AM, David Van Horn <***@backcountryaccess.com> wrote:
>> It might be worth noting that Crystals != Resonators != Oscillators.
>>
>> Resonators frequently include the capacitors they need to work. Generally looser tolerance than crystals.
>>
>>
>> Crystals generally need external capacitors to work in a parallel
>> resonant circuit, and the correct C value is (2 * Cspec) - Cstray
>> Ex: for a 22pF crystal, and assuming 6pF for stray capacitance, use (2*22)-6=38pf so use 39pF.
>> Despite what you may read, the capacitor value is driven by the crystal spec sheet and NOT the chip data sheet!
>> https://www.foxonline.com/pdfs/xtaldesignnotes.pdf
>> If the chip data sheet calls out a capacitance, then they MAY be telling you to use a crystal designed for that load capacitance, or they may have capitulated to hordes of hobbyists demanding that they show cap values in their data sheets.
>> If the caps are correct, then the crystal will run at the correct frequency in circuit. If it's off more than the data sheet tolerance, then you have the wrong caps.
>>
>>
>> Oscillators take power and ground and have an output pin that gives you a signal.
>>
>> --
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>> http://mailman.mit.edu/mailman/listinfo/piclist
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[David Van Horn]

Might not be enough loop gain then. You should be able to put a significant amount of resistance in series and still have it start and run under all conditions.

Way back in the archives you'll find my little adventure with the ATMEGA128 and it's low power "Vittoz" oscillator.
Long story short, Atmel gave no guidance on selecting the crystals, and in low power mode it turned out that the oscillator would run just fine, but the amplitude was low and some parts of the chip sometimes didn't clock. (!) USART baud rates were a little slow, and we had some non-deterministic code execution.

Someone else over-rode my decision not to use the low power mode, and it caused us nothing but grief until we isolated the problem.
The only way to recover was to reprogram and change the fuses back to normal mode.


-----Original Message-----
From: piclist-***@mit.edu <piclist-***@mit.edu> On Behalf Of Manu Abraham
Sent: Friday, September 21, 2018 1:51 PM
To: Microcontroller discussion list - Public. <***@mit.edu>
Subject: Re: EE testing a crystal

Even more fun is the NX5032GA, It has a CL=8pF. With the 4060 it works beautifully without any CL. I guess the stray capacitance was probably around 4pF or so. That was before soldering; It could've changed. CL, I guess is unlikely an issue here, even without CL, the ABM8G shows no life.

On Sat, Sep 22, 2018 at 12:53 AM, David Van Horn <***@backcountryaccess.com> wrote:
> These things frequently come up, and some people don't understand the differences.
> Maybe that comment will be useful when someone searches up this thread.
>
> 10pF is fun, do you know what your strays are?
> The cap value then should be 20pF - Cstray = ??
>
> 10pF cap is likely a bit light, unless your strays are large.
>
>
> -----Original Message-----
> From: piclist-***@mit.edu <piclist-***@mit.edu> On Behalf Of
> Manu Abraham
> Sent: Friday, September 21, 2018 1:08 PM
> To: Microcontroller discussion list - Public. <***@mit.edu>
> Subject: Re: EE testing a crystal
>
> Hi David,
>
> Aware of the differences between crystals, resonators, oscillators.
>
> That said, ABM8G is a crystal, not a resonator.
> "ULTRA MINIATURE CERAMIC GLASS SEALED SMD CRYSTAL"
> And it has a Load capacitance CL=10pF
>
> If you look at the outline drawing, it indeed shows a crystal and not a resonator.
>
> The crystal has 2 shielding pins for GND, but not for any power.
> That's why it has 2 additional pins, for GND.
>
> I believe you took it for a resonator, due to the resonators folder embedded in the link ?
>
> The capacitance I am using is indeed 10pF C0G
> http://www.avx.com/products/ceramic-capacitors/surface-mount/c0g-np0-d
> ielectric/
>
>
> Thanks,
>
> Manu
>
>
>
> On Sat, Sep 22, 2018 at 12:26 AM, David Van Horn <***@backcountryaccess.com> wrote:
>> It might be worth noting that Crystals != Resonators != Oscillators.
>>
>> Resonators frequently include the capacitors they need to work. Generally looser tolerance than crystals.
>>
>>
>> Crystals generally need external capacitors to work in a parallel
>> resonant circuit, and the correct C value is (2 * Cspec) - Cstray
>> Ex: for a 22pF crystal, and assuming 6pF for stray capacitance, use (2*22)-6=38pf so use 39pF.
>> Despite what you may read, the capacitor value is driven by the crystal spec sheet and NOT the chip data sheet!
>> https://www.foxonline.com/pdfs/xtaldesignnotes.pdf
>> If the chip data sheet calls out a capacitance, then they MAY be telling you to use a crystal designed for that load capacitance, or they may have capitulated to hordes of hobbyists demanding that they show cap values in their data sheets.
>> If the caps are correct, then the crystal will run at the correct frequency in circuit. If it's off more than the data sheet tolerance, then you have the wrong caps.
>>
>>
>> Oscillators take power and ground and have an output pin that gives you a signal.
>>
>> --
>> http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive
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>> http://mailman.mit.edu/mailman/listinfo/piclist
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[99guspuppet]

I have been the pleased ( hope to remain that way ) user of an Abbott Freestyle Libre CGM. The sensors go on your arm and monitors the glucose level of my blood. A reader extracts data from the sensor. The sensor sticks a metal probe under my skin and lasts for 10 days ( with a 12 hr warmup period ). I hear that a just released updated system extends the sensor use period to 14 days and the sensor requires a 1 hour warmup.

The same devices are slightly different in performance from country to country ( due to regulations I believe ).

I was having trouble with my reader seeing my sensor. The sensor would work for a day or two and then get harder to link up with reader. It was supposed to work like most NFC….. wave the reader a few centimeters from the sensor. I have deconstructed a used sensor and it does have an on-board battery. The sensor is about 3cm in diameter.

I wondered if my arm had some characteristic that absorbed the signal. Or my clothes. Or my attitude.

Then I took my reader and laid it on the counter and folded aluminum foil 4 times and laid it over the reader. I pressed the foil around the reader to form a cavity the reader sat in. Then I used expanding foam to make the backside of the foil rigid. Now I could lay the reader in the cavity and hold it with rubber bands. The foil is 20cm by 30cm. The orange dots are pieces of plastic that help hold the reader.

( see photo at https://photos.app.goo.gl/7eunAMe9unH9Tboz9 )

With the foil the reader never fails to link with the sensor and transfer data. I guess I don’t understand how Near Field physics work ……… Any comments are appreciated.

Gus in Denver 2018m09d23

( Since I got the CGM [ last part of July ] ….. I started eating a new range of foods …. my blood glucose level has dropped into the normal range ….. I rarely use insulin and I have lost 12 kilograms. )
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[Isaac M. Bavaresco]

Gus,


The foil should act as a shorted turn in the antenna and should
dissipate some of the RF energy as heat.

It is interesting that the communication worked better with it, I would
bet the opposite. Perhaps that's because the foil is very thin and have
a large impedance in this particular frequency.

It is always a problem when our clients want to install RFID readers in
equipments with full metal cases. Many try to use small openings barely
larger than the antenna but the result is usually poor.

They work best when the opening is quite a bit larger than the antenna
and the antenna is supported in the middle of a piece of acrylic
centered on the opening.

Sticking RFID antennas directly over metal surfaces gives also very poor
result. A simple solution is placing a thick plastic spacer between the
surface and the antenna.


Cheers,

Isaac


Em 23/09/2018 05:41, 99guspuppet escreveu:
> I have been the pleased ( hope to remain that way ) user of an Abbott Freestyle Libre CGM. The sensors go on your arm and monitors the glucose level of my blood. A reader extracts data from the sensor. The sensor sticks a metal probe under my skin and lasts for 10 days ( with a 12 hr warmup period ). I hear that a just released updated system extends the sensor use period to 14 days and the sensor requires a 1 hour warmup.
>
> The same devices are slightly different in performance from country to country ( due to regulations I believe ).
>
> I was having trouble with my reader seeing my sensor. The sensor would work for a day or two and then get harder to link up with reader. It was supposed to work like most NFC….. wave the reader a few centimeters from the sensor. I have deconstructed a used sensor and it does have an on-board battery. The sensor is about 3cm in diameter.
>
> I wondered if my arm had some characteristic that absorbed the signal. Or my clothes. Or my attitude.
>
> Then I took my reader and laid it on the counter and folded aluminum foil 4 times and laid it over the reader. I pressed the foil around the reader to form a cavity the reader sat in. Then I used expanding foam to make the backside of the foil rigid. Now I could lay the reader in the cavity and hold it with rubber bands. The foil is 20cm by 30cm. The orange dots are pieces of plastic that help hold the reader.
>
> ( see photo at https://photos.app.goo.gl/7eunAMe9unH9Tboz9 )
>
> With the foil the reader never fails to link with the sensor and transfer data. I guess I don’t understand how Near Field physics work ……… Any comments are appreciated.
>
> Gus in Denver 2018m09d23
>
> ( Since I got the CGM [ last part of July ] ….. I started eating a new range of foods …. my blood glucose level has dropped into the normal range ….. I rarely use insulin and I have lost 12 kilograms. )


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[Jean-Paul Louis]

Manu,

I am not sure how you drive the crystal, but a lot of designers recommend a circuit like the one attached.



> On Sep 21, 2018, at 4:08 PM, David Van Horn <***@backcountryaccess.com> wrote:
>
>

Just my $0.02,

Jean-Paul
N1JPL



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[Bob Blick]

Hi Manu,

I did a survey of resonators a few years back, and basically there are some resonator types that require more oscillator gain to operate.

If you need it to work with your 4060 you might need to make a separate oscillator using multiple gate sections in series.

Cheerful regards,

Bob

P.S. fixed tag. You need a beginning square bracket.
________________________________________
From: piclist-***@mit.edu <piclist-***@mit.edu> on behalf of Manu Abraham
Sent: Friday, September 21, 2018 9:55 AM
To: Microcontroller discussion list - Public.
Subject: EE testing a crystal

Hi,

I have the following crystal, with a frequency of 12MHz.

https://abracon.com/Resonators/ABM8G.pdf

Soldered one of these onto the desired PCB, thought of testing the
crystal using a HEF4060B by connecting between pins 9 and 10, the
crude test which has worked over the years.

Sadly there were no oscillations at all.

The next thought was to do a dead bug style, the crystal. Did that
too, but there seems to be no life at all.

As a result, thinking that the crystal could be dead, tried a brand
new exactly same ABM8G crystal in the dead bug style, which also
showed no signs of life.

Tried a 7.3728MHx crystal in it's position, that does show a clean
7.3728MHz oscillation


I am just scratching my head, lost in thoughts.

Any suggestions, anyone ?

Thanks,

Manu


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[Manu Abraham]

Hi Bob,

Thanks for the quick reply. I was wondering something like that,
but could not really get a foot on the topic where to start looking.

Why would it need more gates ? Larger delay ?

Additionally, I tried another 12MHz crystal with the 4060, that does appear
to work. NX5032GA-12MHZ-STD-CSK-4

http://www.ndk.com/images/products/catalog/c_NX5032GA_e.pdf

But unfortunately, I cannot replace the ABM8G with the NX5032, since it has
a different footprint. Feel really frustrated. :-/

That said, using a Piccolo http://www.ti.com/lit/ds/symlink/tms320f28069m.pdf

I cannot really add any gates in there as it has a built in oscillator.
Have been trying to debug why the oscillator block wont become alive. :-)

This was the whole scenario, that I've trying to debug with the 4060.

Scratching my head still.

Thanks,

Manu



On Fri, Sep 21, 2018 at 10:53 PM, Bob Blick <***@outlook.com> wrote:
> Hi Manu,
>
> I did a survey of resonators a few years back, and basically there are some resonator types that require more oscillator gain to operate.
>
> If you need it to work with your 4060 you might need to make a separate oscillator using multiple gate sections in series.
>
> Cheerful regards,
>
> Bob
>
> P.S. fixed tag. You need a beginning square bracket.
> ________________________________________
> From: piclist-***@mit.edu <piclist-***@mit.edu> on behalf of Manu Abraham
> Sent: Friday, September 21, 2018 9:55 AM
> To: Microcontroller discussion list - Public.
> Subject: EE testing a crystal
>
> Hi,
>
> I have the following crystal, with a frequency of 12MHz.
>
> https://abracon.com/Resonators/ABM8G.pdf
>
> Soldered one of these onto the desired PCB, thought of testing the
> crystal using a HEF4060B by connecting between pins 9 and 10, the
> crude test which has worked over the years.
>
> Sadly there were no oscillations at all.
>
> The next thought was to do a dead bug style, the crystal. Did that
> too, but there seems to be no life at all.
>
> As a result, thinking that the crystal could be dead, tried a brand
> new exactly same ABM8G crystal in the dead bug style, which also
> showed no signs of life.
>
> Tried a 7.3728MHx crystal in it's position, that does show a clean
> 7.3728MHz oscillation
>
>
> I am just scratching my head, lost in thoughts.
>
> Any suggestions, anyone ?
>
> Thanks,
>
> Manu
>
>
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[Bob Blick]

Hi Manu,

I have long suspected that the reasons certain types of crystals and resonators don't work in every application are the amount of phase shift or else the impedance, so it all ends up being too lossy to oscillate. But if you add more capacitance to push the phase, then you need more gain, which you may not have had enough to begin with.

By using multiple gates in series, you get both more gain and more phase shift, and it may work perfectly.

Cheerful regards, Bob

________________________________________
From: piclist-***@mit.edu <piclist-***@mit.edu> on behalf of Manu Abraham
Sent: Friday, September 21, 2018 10:42 AM
To: Microcontroller discussion list - Public.
Subject: Re: [EE] testing a crystal

Hi Bob,

Thanks for the quick reply. I was wondering something like that,
but could not really get a foot on the topic where to start looking.

Why would it need more gates ? Larger delay ?

Additionally, I tried another 12MHz crystal with the 4060, that does appear
to work. NX5032GA-12MHZ-STD-CSK-4

http://www.ndk.com/images/products/catalog/c_NX5032GA_e.pdf

But unfortunately, I cannot replace the ABM8G with the NX5032, since it has
a different footprint. Feel really frustrated. :-/

That said, using a Piccolo http://www.ti.com/lit/ds/symlink/tms320f28069m.pdf

I cannot really add any gates in there as it has a built in oscillator.
Have been trying to debug why the oscillator block wont become alive. :-)

This was the whole scenario, that I've trying to debug with the 4060.

Scratching my head still.

Thanks,

Manu



On Fri, Sep 21, 2018 at 10:53 PM, Bob Blick wrote:
> Hi Manu,
>
> I did a survey of resonators a few years back, and basically there are some resonator types that require more oscillator gain to operate.
>
> If you need it to work with your 4060 you might need to make a separate oscillator using multiple gate sections in series.
>
> Cheerful regards,
>
> Bob
>
> P.S. fixed tag. You need a beginning square bracket.
> ________________________________________
> From: piclist-***@mit.edu <piclist-***@mit.edu> on behalf of Manu Abraham
> Sent: Friday, September 21, 2018 9:55 AM
> To: Microcontroller discussion list - Public.
> Subject: EE testing a crystal
>
> Hi,
>
> I have the following crystal, with a frequency of 12MHz.
>
> https://abracon.com/Resonators/ABM8G.pdf
>
> Soldered one of these onto the desired PCB, thought of testing the
> crystal using a HEF4060B by connecting between pins 9 and 10, the
> crude test which has worked over the years.
>
> Sadly there were no oscillations at all.
>
> The next thought was to do a dead bug style, the crystal. Did that
> too, but there seems to be no life at all.
>
> As a result, thinking that the crystal could be dead, tried a brand
> new exactly same ABM8G crystal in the dead bug style, which also
> showed no signs of life.
>
> Tried a 7.3728MHx crystal in it's position, that does show a clean
> 7.3728MHz oscillation
>
>
> I am just scratching my head, lost in thoughts.
>
> Any suggestions, anyone ?
>
> Thanks,
>
> Manu

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[Manu Abraham]

Hi Bob,

Your comment makes perfect sense. So, I suppose the equivalent series
resistance is the key player that's acting in such a situation,
Probably ?

In the case of the ABM8G it has about 120 ohms, while the NDK NX5032GA
has about 100 ohms.
But that said, the datasheet spec says that the ABM8G needs a drive
level of 10uW, while the NX5032 needs about 50uW. The NX5032 works
while the ABM8G does not. Slightly confusing, at least the datasheets
does not make any parameter look in a much contrasting way, confusing
when you look at the datasheet.

Instead of the 4060, let me try wiring a few gates instead and try the
veroboard method of testing the crystal.

Thanks,

Manu


On Sat, Sep 22, 2018 at 1:46 AM, Bob Blick <***@outlook.com> wrote:
> Hi Manu,
>
> I have long suspected that the reasons certain types of crystals and resonators don't work in every application are the amount of phase shift or else the impedance, so it all ends up being too lossy to oscillate. But if you add more capacitance to push the phase, then you need more gain, which you may not have had enough to begin with.
>
> By using multiple gates in series, you get both more gain and more phase shift, and it may work perfectly.
>
> Cheerful regards, Bob
>
> ________________________________________
> From: piclist-***@mit.edu <piclist-***@mit.edu> on behalf of Manu Abraham
> Sent: Friday, September 21, 2018 10:42 AM
> To: Microcontroller discussion list - Public.
> Subject: Re: [EE] testing a crystal
>
> Hi Bob,
>
> Thanks for the quick reply. I was wondering something like that,
> but could not really get a foot on the topic where to start looking.
>
> Why would it need more gates ? Larger delay ?
>
> Additionally, I tried another 12MHz crystal with the 4060, that does appear
> to work. NX5032GA-12MHZ-STD-CSK-4
>
> http://www.ndk.com/images/products/catalog/c_NX5032GA_e.pdf
>
> But unfortunately, I cannot replace the ABM8G with the NX5032, since it has
> a different footprint. Feel really frustrated. :-/
>
> That said, using a Piccolo http://www.ti.com/lit/ds/symlink/tms320f28069m.pdf
>
> I cannot really add any gates in there as it has a built in oscillator.
> Have been trying to debug why the oscillator block wont become alive. :-)
>
> This was the whole scenario, that I've trying to debug with the 4060.
>
> Scratching my head still.
>
> Thanks,
>
> Manu
>
>
>
> On Fri, Sep 21, 2018 at 10:53 PM, Bob Blick wrote:
>> Hi Manu,
>>
>> I did a survey of resonators a few years back, and basically there are some resonator types that require more oscillator gain to operate.
>>
>> If you need it to work with your 4060 you might need to make a separate oscillator using multiple gate sections in series.
>>
>> Cheerful regards,
>>
>> Bob
>>
>> P.S. fixed tag. You need a beginning square bracket.
>> ________________________________________
>> From: piclist-***@mit.edu <piclist-***@mit.edu> on behalf of Manu Abraham
>> Sent: Friday, September 21, 2018 9:55 AM
>> To: Microcontroller discussion list - Public.
>> Subject: EE testing a crystal
>>
>> Hi,
>>
>> I have the following crystal, with a frequency of 12MHz.
>>
>> https://abracon.com/Resonators/ABM8G.pdf
>>
>> Soldered one of these onto the desired PCB, thought of testing the
>> crystal using a HEF4060B by connecting between pins 9 and 10, the
>> crude test which has worked over the years.
>>
>> Sadly there were no oscillations at all.
>>
>> The next thought was to do a dead bug style, the crystal. Did that
>> too, but there seems to be no life at all.
>>
>> As a result, thinking that the crystal could be dead, tried a brand
>> new exactly same ABM8G crystal in the dead bug style, which also
>> showed no signs of life.
>>
>> Tried a 7.3728MHx crystal in it's position, that does show a clean
>> 7.3728MHz oscillation
>>
>>
>> I am just scratching my head, lost in thoughts.
>>
>> Any suggestions, anyone ?
>>
>> Thanks,
>>
>> Manu
>
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[Clint Jay]

Hmm, i wonder if it’s possible you’re overdriving the ABM8G and damaging
it...

On Fri, 21 Sep 2018 at 21:51, Manu Abraham <***@gmail.com> wrote:

> Hi Bob,
>
> Your comment makes perfect sense. So, I suppose the equivalent series
> resistance is the key player that's acting in such a situation,
> Probably ?
>
> In the case of the ABM8G it has about 120 ohms, while the NDK NX5032GA
> has about 100 ohms.
> But that said, the datasheet spec says that the ABM8G needs a drive
> level of 10uW, while the NX5032 needs about 50uW. The NX5032 works
> while the ABM8G does not. Slightly confusing, at least the datasheets
> does not make any parameter look in a much contrasting way, confusing
> when you look at the datasheet.
>
> Instead of the 4060, let me try wiring a few gates instead and try the
> veroboard method of testing the crystal.
>
> Thanks,
>
> Manu
>
>
> On Sat, Sep 22, 2018 at 1:46 AM, Bob Blick <***@outlook.com> wrote:
> > Hi Manu,
> >
> > I have long suspected that the reasons certain types of crystals and
> resonators don't work in every application are the amount of phase shift or
> else the impedance, so it all ends up being too lossy to oscillate. But if
> you add more capacitance to push the phase, then you need more gain, which
> you may not have had enough to begin with.
> >
> > By using multiple gates in series, you get both more gain and more phase
> shift, and it may work perfectly.
> >
> > Cheerful regards, Bob
> >
> > ________________________________________
> > From: piclist-***@mit.edu <piclist-***@mit.edu> on behalf of
> Manu Abraham
> > Sent: Friday, September 21, 2018 10:42 AM
> > To: Microcontroller discussion list - Public.
> > Subject: Re: [EE] testing a crystal
> >
> > Hi Bob,
> >
> > Thanks for the quick reply. I was wondering something like that,
> > but could not really get a foot on the topic where to start looking.
> >
> > Why would it need more gates ? Larger delay ?
> >
> > Additionally, I tried another 12MHz crystal with the 4060, that does
> appear
> > to work. NX5032GA-12MHZ-STD-CSK-4
> >
> > http://www.ndk.com/images/products/catalog/c_NX5032GA_e.pdf
> >
> > But unfortunately, I cannot replace the ABM8G with the NX5032, since it
> has
> > a different footprint. Feel really frustrated. :-/
> >
> > That said, using a Piccolo
> http://www.ti.com/lit/ds/symlink/tms320f28069m.pdf
> >
> > I cannot really add any gates in there as it has a built in oscillator.
> > Have been trying to debug why the oscillator block wont become alive. :-)
> >
> > This was the whole scenario, that I've trying to debug with the 4060.
> >
> > Scratching my head still.
> >
> > Thanks,
> >
> > Manu
> >
> >
> >
> > On Fri, Sep 21, 2018 at 10:53 PM, Bob Blick wrote:
> >> Hi Manu,
> >>
> >> I did a survey of resonators a few years back, and basically there are
> some resonator types that require more oscillator gain to operate.
> >>
> >> If you need it to work with your 4060 you might need to make a separate
> oscillator using multiple gate sections in series.
> >>
> >> Cheerful regards,
> >>
> >> Bob
> >>
> >> P.S. fixed tag. You need a beginning square bracket.
> >> ________________________________________
> >> From: piclist-***@mit.edu <piclist-***@mit.edu> on behalf of
> Manu Abraham
> >> Sent: Friday, September 21, 2018 9:55 AM
> >> To: Microcontroller discussion list - Public.
> >> Subject: EE testing a crystal
> >>
> >> Hi,
> >>
> >> I have the following crystal, with a frequency of 12MHz.
> >>
> >> https://abracon.com/Resonators/ABM8G.pdf
> >>
> >> Soldered one of these onto the desired PCB, thought of testing the
> >> crystal using a HEF4060B by connecting between pins 9 and 10, the
> >> crude test which has worked over the years.
> >>
> >> Sadly there were no oscillations at all.
> >>
> >> The next thought was to do a dead bug style, the crystal. Did that
> >> too, but there seems to be no life at all.
> >>
> >> As a result, thinking that the crystal could be dead, tried a brand
> >> new exactly same ABM8G crystal in the dead bug style, which also
> >> showed no signs of life.
> >>
> >> Tried a 7.3728MHx crystal in it's position, that does show a clean
> >> 7.3728MHz oscillation
> >>
> >>
> >> I am just scratching my head, lost in thoughts.
> >>
> >> Any suggestions, anyone ?
> >>
> >> Thanks,
> >>
> >> Manu
> >
> > --
> > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive
> > View/change your membership options at
> > http://mailman.mit.edu/mailman/listinfo/piclist
>
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[Manu Abraham]

An update:

Got another set of ABM8G. Those worked directly with the
Piccolo DSP controller. I guess that was a batch of bad
crystals, what I got previously.

Will update this thread, as more light is shed into it.

Cheers,

Manu

On Sat, Sep 22, 2018 at 1:47 AM Bob Blick <***@outlook.com> wrote:
>
> Hi Manu,
>
> I have long suspected that the reasons certain types of crystals and resonators don't work in every application are the amount of phase shift or else the impedance, so it all ends up being too lossy to oscillate. But if you add more capacitance to push the phase, then you need more gain, which you may not have had enough to begin with.
>
> By using multiple gates in series, you get both more gain and more phase shift, and it may work perfectly.
>
> Cheerful regards, Bob
>
> ________________________________________
> From: piclist-***@mit.edu <piclist-***@mit.edu> on behalf of Manu Abraham
> Sent: Friday, September 21, 2018 10:42 AM
> To: Microcontroller discussion list - Public.
> Subject: Re: [EE] testing a crystal
>
> Hi Bob,
>
> Thanks for the quick reply. I was wondering something like that,
> but could not really get a foot on the topic where to start looking.
>
> Why would it need more gates ? Larger delay ?
>
> Additionally, I tried another 12MHz crystal with the 4060, that does appear
> to work. NX5032GA-12MHZ-STD-CSK-4
>
> http://www.ndk.com/images/products/catalog/c_NX5032GA_e.pdf
>
> But unfortunately, I cannot replace the ABM8G with the NX5032, since it has
> a different footprint. Feel really frustrated. :-/
>
> That said, using a Piccolo http://www.ti.com/lit/ds/symlink/tms320f28069m.pdf
>
> I cannot really add any gates in there as it has a built in oscillator.
> Have been trying to debug why the oscillator block wont become alive. :-)
>
> This was the whole scenario, that I've trying to debug with the 4060.
>
> Scratching my head still.
>
> Thanks,
>
> Manu
>
>
>
> On Fri, Sep 21, 2018 at 10:53 PM, Bob Blick wrote:
> > Hi Manu,
> >
> > I did a survey of resonators a few years back, and basically there are some resonator types that require more oscillator gain to operate.
> >
> > If you need it to work with your 4060 you might need to make a separate oscillator using multiple gate sections in series.
> >
> > Cheerful regards,
> >
> > Bob
> >
> > P.S. fixed tag. You need a beginning square bracket.
> > ________________________________________
> > From: piclist-***@mit.edu <piclist-***@mit.edu> on behalf of Manu Abraham
> > Sent: Friday, September 21, 2018 9:55 AM
> > To: Microcontroller discussion list - Public.
> > Subject: EE testing a crystal
> >
> > Hi,
> >
> > I have the following crystal, with a frequency of 12MHz.
> >
> > https://abracon.com/Resonators/ABM8G.pdf
> >
> > Soldered one of these onto the desired PCB, thought of testing the
> > crystal using a HEF4060B by connecting between pins 9 and 10, the
> > crude test which has worked over the years.
> >
> > Sadly there were no oscillations at all.
> >
> > The next thought was to do a dead bug style, the crystal. Did that
> > too, but there seems to be no life at all.
> >
> > As a result, thinking that the crystal could be dead, tried a brand
> > new exactly same ABM8G crystal in the dead bug style, which also
> > showed no signs of life.
> >
> > Tried a 7.3728MHx crystal in it's position, that does show a clean
> > 7.3728MHz oscillation
> >
> >
> > I am just scratching my head, lost in thoughts.
> >
> > Any suggestions, anyone ?
> >
> > Thanks,
> >
> > Manu
>
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> View/change your membership options at
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[AB Pearce - UKRI STFC]

> An update:
>
> Got another set of ABM8G. Those worked directly with the Piccolo DSP controller.
> I guess that was a batch of bad crystals, what I got previously.
>
> Will update this thread, as more light is shed into it.

Probably find the box was dropped from a significant height somewhere between the manufacturer and you.



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[John Coppens]

On Fri, 21 Sep 2018 23:12:43 +0530
Manu Abraham <***@gmail.com> wrote:

> Hi Bob,
>
> Thanks for the quick reply. I was wondering something like that,
> but could not really get a foot on the topic where to start looking.
>
> Why would it need more gates ? Larger delay ?
>
>>
Beware of the parallel resistor. If it's too low, some xtal won't
start. But oscillators like the 4060 do need a 4.7 to 10 MOhm resistor,
else they won't start because they're not in their linear zone.

John
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[Brooke Clarke]

Hi Gus:

NFC works in the 13.56 MHz ISM band (Wiki <https://en.wikipedia.org/wiki/ISM_band#Frequency_allocation>).
There are a couple of ways this frequency is used.
In one case the 13.56 MHz signal powers the RF ID card and that power is used to modulate the 13.56 Mhz signal.  For
example NFC on cell phones or some RFID cards.
https://www.prc68.com/I/CellPhones.html#NFC
https://www.prc68.com/I/RFID.shtml

In another case the 13.56 MHz signal supplies power to circuitry that includes a VHF or UHF transmitter that sends
digital information,  I suspect your device is like this and that would explain why it works better with the foil,
acting as a reflector for a VHF or UHF signal.  If you have a way to sense signal strength you could try different
separations between the foil and device to see which works best.  Or if you have access to a spectrum analyzer see what
the VHF/UHF frequency is.  Or check for patents.

--
Have Fun,

Brooke Clarke, N6GCE
https://www.PRC68.com
https://www.end2partygovernment.com/2012Issues.html
axioms:
1. The extent to which you can fix or improve something will be limited by how well you understand how it works.
2. Everybody, with no exceptions, holds false beliefs.

-------- Original Message --------
> You can reach the person managing the list at

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[99guspuppet]

Thank you Brook and Isaac

The sensor is said to work with Android phones using a special app. This implies that RF communications must be limited to those that an Android phone can send and receive.

Best

Gus in Denver area
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[RussellMc]

A possibility: Pad view and internal diagram are shown from bottom and top
of PCB respectively.
Is there any chance that you have connected to the two ground pads rather
than to the crystal.
A continuity test would easily confirm which is which.


Russell


>
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[Manu Abraham]

Russell,

That possibility can be ruled out. When there were no oscillations, this was my
exact thought. First thing that I did was a continuity check between the GND
pins. But to my utter dismay, none of the pins showed any continuity between
them. What I can guess is that, the GND pins are simply dummy pins, which
guarantees a guard ring on the PCB and nothing more than that.

The next thing what I tried was to do the dead bug style, in all possible ways.
But, heck, in none of the possible ways the crystal did oscillate.

At this point, thought was probably a dead crystal and wanted to try another
one. But that crystal also had exactly the same behaviour. It's slightly hard to
digest the fact that two devices could be faulty. Thought it would be a gain
related issue as in a previous post, had an option to add in a series resistor.
But that also did not show any success.

That said, I had one more crystal, a third one that there, wanted to try that.
But bad luck, while peeling off the tape, the bug flew away. :-/
Tried hard, but the bug escaped for it's freedom and life.

That said, ordered some crystals from NDK this time, this did work without
any fiddling around. The NDK crystals are slightly more expensive, but the
tolerances are much lesser. Fortunately the footprint is identical.

To get the curiosity satisfied, will do a multi gate series oscillator
as Bob was
suggesting, but even if that works, I will not be able to use that configuration
on the controller, due to the builtin oscillator as well as the PCB layout.

I have seen crystals fail, but seeing brand new crystals dead for the
first time.

Will update this thread as how things pan out.

Thanks,

Manu



On Tue, Sep 25, 2018 at 7:25 PM, RussellMc <***@gmail.com> wrote:
> A possibility: Pad view and internal diagram are shown from bottom and top
> of PCB respectively.
> Is there any chance that you have connected to the two ground pads rather
> than to the crystal.
> A continuity test would easily confirm which is which.
>
>
> Russell
>
>
>>
> --
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> View/change your membership options at
> http://mailman.mit.edu/mailman/listinfo/piclist
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[David Van Horn]

Can you say the part numbers of the NDK part and the one that doesn't work?
A comparison of the data sheets might reveal something.

-----Original Message-----
From: piclist-***@mit.edu <piclist-***@mit.edu> On Behalf Of Manu Abraham
Sent: Tuesday, September 25, 2018 9:19 AM
To: Microcontroller discussion list - Public. <***@mit.edu>
Subject: Re: EE testing a crystal

Russell,

That possibility can be ruled out. When there were no oscillations, this was my exact thought. First thing that I did was a continuity check between the GND pins. But to my utter dismay, none of the pins showed any continuity between them. What I can guess is that, the GND pins are simply dummy pins, which guarantees a guard ring on the PCB and nothing more than that.

The next thing what I tried was to do the dead bug style, in all possible ways.
But, heck, in none of the possible ways the crystal did oscillate.

At this point, thought was probably a dead crystal and wanted to try another one. But that crystal also had exactly the same behaviour. It's slightly hard to digest the fact that two devices could be faulty. Thought it would be a gain related issue as in a previous post, had an option to add in a series resistor.
But that also did not show any success.

That said, I had one more crystal, a third one that there, wanted to try that.
But bad luck, while peeling off the tape, the bug flew away. :-/ Tried hard, but the bug escaped for it's freedom and life.

That said, ordered some crystals from NDK this time, this did work without any fiddling around. The NDK crystals are slightly more expensive, but the tolerances are much lesser. Fortunately the footprint is identical.

To get the curiosity satisfied, will do a multi gate series oscillator as Bob was suggesting, but even if that works, I will not be able to use that configuration on the controller, due to the builtin oscillator as well as the PCB layout.

I have seen crystals fail, but seeing brand new crystals dead for the first time.

Will update this thread as how things pan out.

Thanks,

Manu



On Tue, Sep 25, 2018 at 7:25 PM, RussellMc <***@gmail.com> wrote:
> A possibility: Pad view and internal diagram are shown from bottom and
> top of PCB respectively.
> Is there any chance that you have connected to the two ground pads
> rather than to the crystal.
> A continuity test would easily confirm which is which.
>
>
> Russell
>
>
>>
> --
> http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive
> View/change your membership options at
> http://mailman.mit.edu/mailman/listinfo/piclist
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[Manu Abraham]

Hi David,

Both 12MHz crystals

http://www.ndk.com/images/products/catalog/c_NX3225GA-STD-CRG-2_e.pdf
https://abracon.com/Resonators/ABM8G.pdf


This one also did work, but using the hef4060, but has a different footprint
http://www.ndk.com/images/products/catalog/c_NX5032GA_e.pdf



On Tue, Sep 25, 2018 at 8:53 PM, David Van Horn
<***@backcountryaccess.com> wrote:
> Can you say the part numbers of the NDK part and the one that doesn't work?
> A comparison of the data sheets might reveal something.
>
> -----Original Message-----
> From: piclist-***@mit.edu <piclist-***@mit.edu> On Behalf Of Manu Abraham
> Sent: Tuesday, September 25, 2018 9:19 AM
> To: Microcontroller discussion list - Public. <***@mit.edu>
> Subject: Re: EE testing a crystal
>
> Russell,
>
> That possibility can be ruled out. When there were no oscillations, this was my exact thought. First thing that I did was a continuity check between the GND pins. But to my utter dismay, none of the pins showed any continuity between them. What I can guess is that, the GND pins are simply dummy pins, which guarantees a guard ring on the PCB and nothing more than that.
>
> The next thing what I tried was to do the dead bug style, in all possible ways.
> But, heck, in none of the possible ways the crystal did oscillate.
>
> At this point, thought was probably a dead crystal and wanted to try another one. But that crystal also had exactly the same behaviour. It's slightly hard to digest the fact that two devices could be faulty. Thought it would be a gain related issue as in a previous post, had an option to add in a series resistor.
> But that also did not show any success.
>
> That said, I had one more crystal, a third one that there, wanted to try that.
> But bad luck, while peeling off the tape, the bug flew away. :-/ Tried hard, but the bug escaped for it's freedom and life.
>
> That said, ordered some crystals from NDK this time, this did work without any fiddling around. The NDK crystals are slightly more expensive, but the tolerances are much lesser. Fortunately the footprint is identical.
>
> To get the curiosity satisfied, will do a multi gate series oscillator as Bob was suggesting, but even if that works, I will not be able to use that configuration on the controller, due to the builtin oscillator as well as the PCB layout.
>
> I have seen crystals fail, but seeing brand new crystals dead for the first time.
>
> Will update this thread as how things pan out.
>
> Thanks,
>
> Manu
>
>
>
> On Tue, Sep 25, 2018 at 7:25 PM, RussellMc <***@gmail.com> wrote:
>> A possibility: Pad view and internal diagram are shown from bottom and
>> top of PCB respectively.
>> Is there any chance that you have connected to the two ground pads
>> rather than to the crystal.
>> A continuity test would easily confirm which is which.
>>
>>
>> Russell
>>
>>
>>>
>> --
>> http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive
>> View/change your membership options at
>> http://mailman.mit.edu/mailman/listinfo/piclist
> --
> http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist
>
> --
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> View/change your membership options at
> http://mailman.mit.edu/mailman/listinfo/piclist

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[David Van Horn]

The most obvious difference I see is the ESR of the NDK part is about double that of the Abracon part.
The NDK spec here is a little confusing as I see 200 or 100 as ESRs for 12 MHz. You're right on the dividing line.
Looking at both top views it's the same pinout.
I would definitely ground the case for these or any similar parts.

Suggested drive levels are the same though the max on the NDK is better.

Are both parts that you have parallel resonant? Decode the exact part number on the Abracon, the NDK doesn't show their "secret decoder ring" but Abracon does.

Both should oscillate though, a series one just won't get to exactly the right freq in a parallel circuit.

I'm not seeing any fundamental "That won't oscillate" issue.



-----Original Message-----
From: piclist-***@mit.edu <piclist-***@mit.edu> On Behalf Of Manu Abraham
Sent: Tuesday, September 25, 2018 9:58 AM
To: Microcontroller discussion list - Public. <***@mit.edu>
Subject: Re: EE testing a crystal

Hi David,

Both 12MHz crystals

http://www.ndk.com/images/products/catalog/c_NX3225GA-STD-CRG-2_e.pdf
https://abracon.com/Resonators/ABM8G.pdf


This one also did work, but using the hef4060, but has a different footprint http://www.ndk.com/images/products/catalog/c_NX5032GA_e.pdf



On Tue, Sep 25, 2018 at 8:53 PM, David Van Horn <***@backcountryaccess.com> wrote:
> Can you say the part numbers of the NDK part and the one that doesn't work?
> A comparison of the data sheets might reveal something.
>
> -----Original Message-----
> From: piclist-***@mit.edu <piclist-***@mit.edu> On Behalf Of
> Manu Abraham
> Sent: Tuesday, September 25, 2018 9:19 AM
> To: Microcontroller discussion list - Public. <***@mit.edu>
> Subject: Re: EE testing a crystal
>
> Russell,
>
> That possibility can be ruled out. When there were no oscillations, this was my exact thought. First thing that I did was a continuity check between the GND pins. But to my utter dismay, none of the pins showed any continuity between them. What I can guess is that, the GND pins are simply dummy pins, which guarantees a guard ring on the PCB and nothing more than that.
>
> The next thing what I tried was to do the dead bug style, in all possible ways.
> But, heck, in none of the possible ways the crystal did oscillate.
>
> At this point, thought was probably a dead crystal and wanted to try another one. But that crystal also had exactly the same behaviour. It's slightly hard to digest the fact that two devices could be faulty. Thought it would be a gain related issue as in a previous post, had an option to add in a series resistor.
> But that also did not show any success.
>
> That said, I had one more crystal, a third one that there, wanted to try that.
> But bad luck, while peeling off the tape, the bug flew away. :-/ Tried hard, but the bug escaped for it's freedom and life.
>
> That said, ordered some crystals from NDK this time, this did work without any fiddling around. The NDK crystals are slightly more expensive, but the tolerances are much lesser. Fortunately the footprint is identical.
>
> To get the curiosity satisfied, will do a multi gate series oscillator as Bob was suggesting, but even if that works, I will not be able to use that configuration on the controller, due to the builtin oscillator as well as the PCB layout.
>
> I have seen crystals fail, but seeing brand new crystals dead for the first time.
>
> Will update this thread as how things pan out.
>
> Thanks,
>
> Manu
>
>
>
> On Tue, Sep 25, 2018 at 7:25 PM, RussellMc <***@gmail.com> wrote:
>> A possibility: Pad view and internal diagram are shown from bottom
>> and top of PCB respectively.
>> Is there any chance that you have connected to the two ground pads
>> rather than to the crystal.
>> A continuity test would easily confirm which is which.
>>
>>
>> Russell
>>
>>
>>>
>> --
>> http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive
>> View/change your membership options at
>> http://mailman.mit.edu/mailman/listinfo/piclist
> --
> http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive
> View/change your membership options at
> http://mailman.mit.edu/mailman/listinfo/piclist
>
> --
> http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive
> View/change your membership options at
> http://mailman.mit.edu/mailman/listinfo/piclist

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[Manu Abraham]

The Abracon part no is ABM8G-12.000MHZ-4Y-T3
The land pattern on the ABM8G is not exactly as shown in the ABM8G,
but looks identical to the one in the NDK datasheet.

The NDK datasheet, talks a bit more on the GND pins, that they are not
internally connected at all.


On Tue, Sep 25, 2018 at 10:02 PM, David Van Horn
<***@backcountryaccess.com> wrote:
> The most obvious difference I see is the ESR of the NDK part is about double that of the Abracon part.
> The NDK spec here is a little confusing as I see 200 or 100 as ESRs for 12 MHz. You're right on the dividing line.
> Looking at both top views it's the same pinout.
> I would definitely ground the case for these or any similar parts.
>
> Suggested drive levels are the same though the max on the NDK is better.
>
> Are both parts that you have parallel resonant? Decode the exact part number on the Abracon, the NDK doesn't show their "secret decoder ring" but Abracon does.
>
> Both should oscillate though, a series one just won't get to exactly the right freq in a parallel circuit.
>
> I'm not seeing any fundamental "That won't oscillate" issue.
>
>
>
> -----Original Message-----
> From: piclist-***@mit.edu <piclist-***@mit.edu> On Behalf Of Manu Abraham
> Sent: Tuesday, September 25, 2018 9:58 AM
> To: Microcontroller discussion list - Public. <***@mit.edu>
> Subject: Re: EE testing a crystal
>
> Hi David,
>
> Both 12MHz crystals
>
> http://www.ndk.com/images/products/catalog/c_NX3225GA-STD-CRG-2_e.pdf
> https://abracon.com/Resonators/ABM8G.pdf
>
>
> This one also did work, but using the hef4060, but has a different footprint http://www.ndk.com/images/products/catalog/c_NX5032GA_e.pdf
>
>
>
> On Tue, Sep 25, 2018 at 8:53 PM, David Van Horn <***@backcountryaccess.com> wrote:
>> Can you say the part numbers of the NDK part and the one that doesn't work?
>> A comparison of the data sheets might reveal something.
>>
>> -----Original Message-----
>> From: piclist-***@mit.edu <piclist-***@mit.edu> On Behalf Of
>> Manu Abraham
>> Sent: Tuesday, September 25, 2018 9:19 AM
>> To: Microcontroller discussion list - Public. <***@mit.edu>
>> Subject: Re: EE testing a crystal
>>
>> Russell,
>>
>> That possibility can be ruled out. When there were no oscillations, this was my exact thought. First thing that I did was a continuity check between the GND pins. But to my utter dismay, none of the pins showed any continuity between them. What I can guess is that, the GND pins are simply dummy pins, which guarantees a guard ring on the PCB and nothing more than that.
>>
>> The next thing what I tried was to do the dead bug style, in all possible ways.
>> But, heck, in none of the possible ways the crystal did oscillate.
>>
>> At this point, thought was probably a dead crystal and wanted to try another one. But that crystal also had exactly the same behaviour. It's slightly hard to digest the fact that two devices could be faulty. Thought it would be a gain related issue as in a previous post, had an option to add in a series resistor.
>> But that also did not show any success.
>>
>> That said, I had one more crystal, a third one that there, wanted to try that.
>> But bad luck, while peeling off the tape, the bug flew away. :-/ Tried hard, but the bug escaped for it's freedom and life.
>>
>> That said, ordered some crystals from NDK this time, this did work without any fiddling around. The NDK crystals are slightly more expensive, but the tolerances are much lesser. Fortunately the footprint is identical.
>>
>> To get the curiosity satisfied, will do a multi gate series oscillator as Bob was suggesting, but even if that works, I will not be able to use that configuration on the controller, due to the builtin oscillator as well as the PCB layout.
>>
>> I have seen crystals fail, but seeing brand new crystals dead for the first time.
>>
>> Will update this thread as how things pan out.
>>
>> Thanks,
>>
>> Manu
>>
>>
>>
>> On Tue, Sep 25, 2018 at 7:25 PM, RussellMc <***@gmail.com> wrote:
>>> A possibility: Pad view and internal diagram are shown from bottom
>>> and top of PCB respectively.
>>> Is there any chance that you have connected to the two ground pads
>>> rather than to the crystal.
>>> A continuity test would easily confirm which is which.
>>>
>>>
>>> Russell
>>>
>>>
>>>>
>>> --
>>> http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive
>>> View/change your membership options at
>>> http://mailman.mit.edu/mailman/listinfo/piclist
>> --
>> http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive
>> View/change your membership options at
>> http://mailman.mit.edu/mailman/listinfo/piclist
>>
>> --
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>> View/change your membership options at
>> http://mailman.mit.edu/mailman/listinfo/piclist
>
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>
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