DAC38J82: Temperature sensor data

Alexander Osipov

Part Number: DAC38J82

Hi all!
I try to read junction temperature of DAC38J82 from config7 register. I use ~100kHz SCLK. And I get high temperature value(96 degrees Celsius(0x6000 value of register)) when chip is only powered(DACCLK is missing) and CONFIG26 register has value 0x01BF. I have next SPI timing diagram when I read config7 register:

I touch chip by finger it is a little warm. Where am I wrong?

over 4 years ago

0 Vijayendra Varma Siddamsetty over 4 years ago

TI__Genius 10505 points

Hi Alexander,

We are looking into your question and will get back to you.

Regards,

Vijay

0 jim s over 4 years ago

TI__Guru* 91947 points

Alexander,

Make sure config26 bit 6 is set to "0" to enable the temp sensor. On our setup, I read back a value of "2D" with the part running with a clock. This is a 2's comp number that corresponds to 45 degrees Celsius after converting it to decimal. I am not sure why you are getting such a high value. Can you verify you are able to read and write to other registers with no problems.

Regards,

Jim

0 Alexander Osipov over 4 years ago in reply to jim s

Prodigy 70 points

Jim, thanks for your reply!
I forgot toggle RESETB pin to reset SIF registers. After that temperature values become normal.

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DAC38J82: Temperature sensor data