DAC80502-01EVM: Data converters forum

Tanaka Yuki

Prodigy 10 points

Part Number: DAC80502-01EVM
Other Parts Discussed in Thread: DAC80502, , DAC80501

Tool/software:

Hello,

I'm testing DAC80501 and DAC80502 on DAC80502-01EVM.

I found the DACs don't work when the VDD is 3.3V by VDD-SEL jumper.

Using external VDD, decrease the VDD from 5.0V, the DAC output level shuts down to 0V when the VDD is 3.60V.

If I increase the VDD voltage, the output goes back. The VREF voltage is stable until VDD = 2.6V. The GAIN setting didn't affect the behavior.

Could anyone please provide some advice? Our application uses 3.3V VDD, and it is an important problem.

Best Regards,

2 days ago

0 Erin Bowrie 2 days ago

TI__Genius 10670 points

Hi Yuki-san,

If the reference is not configured correctly, it will shut the DAC buffers down. For VDD voltages less than 3.6V, please set the "REF-DIV" bit to 1. This is bit 8 in Register 4. With this, the output should enable. Note that the max output in this case will be equal to 1.25V (with the internal reference). If you set the DAC gain to 1, the max output will be 2.5V.

Additionally, the minimum VDD voltage is 2.7V. The device will not work under this voltage.

Thanks,
Erin