DAC80501: SPI configuration code

Hi Emma,

Please share a schematic and a screenshot of a write sequence so we can verify the SPI timings. It is easy to test communication by powering off/on the internal reference and measuring the reference pin to see if the command is working. The reference is powered on by default, so try powering it down and measure the pin. 

Another common reason customer's will not see an output is because they are violating the reference buffer headroom requirements. The reference needs to be between the following voltages based on the VDD and REF-DIV setting used. This is also required when using the 2.5-V internal reference. 

Best,

Katlynne Jones 

Jones,

please see schematic:

and here is the communication waveform:

BR

Emma

Hi Jones,

Thanks for your reply. My customer changed the SPI mode and they can use REF_PWDWN bit to control the level of VREFIO. But still no output on VOUT.

BR

Emma

Thanks, Katlynne will respond after the US 4th of July holiday.

Hi Emma, 

Good to know they can control the reference. Can they try setting the REF-DIV bit to 1 and see if there is any output after writing a value to the DAC data register? 

If not, please share a screenshot of the write to the DAC data register so I can double check that.

Best,

Katlynne Jones