DAC3482: DAC3482IRKD25

murugan ramasamy

Prodigy 155 points

Part Number: DAC3482
Other Parts Discussed in Thread: TPS796

We are facing some issues in DAC3482 operation, Below points are our observations

When DAC power supply is not connected with DAC3482.

1.2V regulators(TPS79601DCQ and TPS79601KTTT) output is 1.2V.

When DAC power supply connected with DAC3482.

1.2V regulators(TPS79601DCQ and TPS79601KTTT) output is increasing from 1.2V to 1.4V.

During this condition DAC is not working.

Above issues we are facing once in a while, But it is major issue for our application.

Please provide your feedback on this issues.

Thanks in advance

over 9 years ago

0 Ebenezer Dwobeng over 9 years ago

TI__Genius 9695 points

Hi Murugan,

We are looking into this and will get back soon with a response.

Thanks,
Eben.

0 Abdallah Obidat over 9 years ago

TI__Intellectual 775 points

Murugan,

Are you using an EVM or is this your design? Could you provide a register dump so that I may inspect your DAC configuration? I do not see the behavior you describe on the DAC EVM...

Regards,

Abdallah

0 murugan ramasamy over 9 years ago in reply to Ebenezer Dwobeng

Prodigy 155 points

Thank you .I m waiting for your feedback

0 murugan ramasamy over 9 years ago in reply to Abdallah Obidat

Prodigy 155 points

Below are the config bit status
config1 0x060E
config16 0x3000
config27 0x0800
config32 0x2201
config0 0x019C
config2 0xF002
config7 0x4063
config36 0x0000
config5 0x0

Hardware wise DAC section is same as EVM.But i can see some variation in DAC power supply LDO’S between different versions of EVM schematic.

Below are my power supply ICs

Input Voltage	LDO Part Number	Output Voltage
3.5V	TPS79601DCQ	3.3V (AVDD)
3.5V	TPS79601DCQ	3.3V (IOVDD)
3.5V	TPS79601DCQ	1.2V (DACVDD)
3.5V	TPS79601DCQ	1.2V (CLKVDD)
3.5V	TPS79601KTTT	1.2V (DIGVDD)

I m doubting on LDOs because its Vref=1.224V.

0 Abdallah Obidat over 9 years ago in reply to murugan ramasamy

TI__Intellectual 775 points

Looking over the config bits you sent, I didn't see anything that stood out. I sent you a private message, if you'd like to contact me via email. I will do some more investigating, regarding the LDOs, but you might want to consider posting on the LDO (TPS796) E2E Forum.

Regards,

Abdallah

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DAC3482: DAC3482IRKD25