Help: AD5422AREZ-REEL REFOUT pin output voltage is abnormal

chenzhouyu

Help: AD5422AREZ-REEL REFOUT pin output voltage is abnormal [Copy link]

Hello everyone!

I encountered a problem. The output of REFOUT of the two batches of AD5422AREZ-REEL was different. The output of REFOUT of the first batch was 4.999V.

The output of the latest batch is only 4.905V, and the peripheral current is as shown below. In the laboratory environment, using the Tektronix PWS2323 power supply, the phenomenon still exists.

Which parameter of the peripheral current is unreasonable? Thank you!
Among them:

+V_DA is 12V input;
C301 is a tantalum capacitor.

呜呼哀哉

You can try raising +V_DA. The input voltage of AD5422 is very high, so the reference output part should be fine even if it is a ceramic 104.

人为现象

There is nothing wrong with the circuit, but the second batch exceeds the specification. I would like to give you some ideas. 1. Use PWS2323 for power supply. If the power supply current is not limited or the voltage drops. 2. Use an oscilloscope to measure whether REFout is stable. 3. Does the circuit board have obvious heat generation? If there is no problem with these three points, please confirm the channel with your supplier.

chenzhouyu

Artificial Phenomenon Published on 2021-7-15 10:39 There is no abnormality in the circuit, but the second batch exceeds the specification sheet, support to give some ideas, 1. The power supply uses PWS2323, if the power supply current is not limited, or...

The power supply has no current limit, the REFOUT ripple and noise are very small, and no heat is generated.