DAC8734: Not Able to get the full scale reading and issue with Zero and Gain settings

Nanjunda M1

Part Number: DAC8734

Hi,

We are using the DAC8734 DAC in our design. We have designed the Ref as 2.5V and for bipolar operation from +5V to -5V.

When we set the output to the maximum extreme (7f ff or 80 00) the values observed are only +4.74 & -4.84.

Also, with writing to the Zero and Gain registers we are not able to observe any difference in the output.

What could be the problem? Can anyone please help ASAP.

Thanks & Regards,

Nanjunda M

0 Akhilesh K over 3 years ago

Hi,

whats the value of AVDD and AVSS? Can you measure the same? Can you measure the reference also on board?

Please note that in bipolar operation, with Ref = 2.5V, AVDD should be 6V and AVSS should be -6V

(For bipolar mode : AVDD ≥ 2×VREF+1V, and AVSS ≤ –2×VREF–1V )

Regards,

0 Nanjunda M1 over 3 years ago in reply to Akhilesh K

Hi Akhilesh,

Thanks for the response.

The AVDD is +5V and AVSS is -5V.

Please note that in bipolar operation, with Ref = 2.5V, AVDD should be 6V and AVSS should be -6V

I will update this and come back on this.

Thanks & Regards,

Nanjunda M

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