Hello, we are developing a new acquisition unit with AD9233, we design the antialea and the FDA chain to drive the ADC.
We product more or less 20 sample (ten layers board with Zynq ecc) but in only one sample we found a 27MHz oscillation (500mVpp) from the converter..
the first time my through was the FDA amplifier which oscillate for that i revome the inductor to isolate the ADC and FDA, and the oscillation goes to 15MHz about (quite sinewave, not perfect) is from the ADC. this signal is common to Vin+ and Vin- and CML.
Could a bad quality capacitor (0402 ) 100nF connected to REFT and REFB do this problem?
Thanks in advance.
Matteo