ADS7951: Max VREF (ABS max)

domenyko

Part Number: ADS7951

Dear all,

I've seen other treads on this topic, but an important spec in the DS is still missing. Which is the ABS MAX value of the REFP pin ?

One of my customer is supplyng the device at 3.3V and it is providing the REFP pin with the same voltage.

The customer does not care too much if there is a degradation of the measurements in this condition, but he needs to know if the part can be damaged.

Usually the Recommended Operating Conditions (max 3V) offer stil some margin. It is the case ? Will the part be damaged if the REFP =3.3V ?

regards,

Domenico

over 7 years ago

0 Vishy Viswanathan over 7 years ago

TI__Mastermind 21685 points

Domenico,
>>>>Will the part be damaged if the REFP =3.3V ?
I will check about this and come back to you.
As I understand, device is designed to operate over REFP = 2V to 3V so REFP = 3.3V is out of spec.

Thanks,
Vishy

0 domenyko over 7 years ago in reply to Vishy Viswanathan

TI__Genius 9655 points

Hi Vishy,

thanks, looking forward for your answer after checking.

regards,

Domenico

0 domenyko over 7 years ago in reply to domenyko

TI__Genius 9655 points

Hi Vishy,

didi you check if the part can be damaged if the REFP =3.3V, when supplied at 3.3V ?

regards,

Domenico

0 Vishy Viswanathan over 7 years ago in reply to domenyko

TI__Mastermind 21685 points

Domenico,
I am waiting for feedback on this. Sorry about the delay. Will followup again and update.
Thanks,
Vishy

0 Vishy Viswanathan over 7 years ago in reply to Vishy Viswanathan

TI__Mastermind 21685 points

Domenico,

We have ESD diodes from REFP pin to AVDD. So as long as AVDD is greater than or equal to REFP voltage, it is unlikely that part will get damaged by 3.3V on REFP pin. But still it is not recommended to power REFP pin from 3.3V supply as it is above maximum operating condition of this device and therefore falls outside data sheet specification for the device.

Note customer cannot use 2xVREF range in this case and has to use 0 to VREF range.

Thanks,
Vishy

0 domenyko over 7 years ago in reply to Vishy Viswanathan

TI__Genius 9655 points

Hi Vishy,

Thanks a lot. This is exactly what I wanted to hear.

The customer is using the device in the 0-Vref region.

Regards,

Domenico

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ADS7951: Max VREF (ABS max)