Hi,
I have some problems using DAC7311.
(1) When the MCU sends different SPI data to U1 of the circuit diagram, SPI CLK=1MHz, SPI data D11~D0: 6EF(hex)~611(hex),the data decreases every 14(hex). Normally, Vout-CH1 will decrease with the data decrease, and the output voltage will also decrease. However, during the data decrease process, the output voltage will occasionally drop to 0.4V, and after 20ms, it will rise back to the normal output voltage. 0.4V is an abnormal output voltage range.
(2) When the same SPI data is sent to U2, U3 and U4 of the circuit diagram, the above (1) situation will not occur.
(3) I checked the SPI data and found no abnormality. I also observed it with an oscilloscope and the level and timing are normal. Could you please tell me where else I can find the problem?
Thank you!
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