Hi, I have a problem with the operation of the AD9735 chip.
We have produced two custom PCBs using these chips. In both there is the same problem. The circuit after switching on works correctly, the signal generated is correct, the circuit reads the configuration, responds, for example, to PD mode, change of current(reg 2,3). However, after some time, usually about 20-40 minutes, the circuit stops working. The output data disappears. The clock is still present, data from the FPGA processor is sent, SPI communication works. The temperature of the chip , measured with a thermocouple-type probe, is about 40 degrees C.
reading registers during correct operation, reading registers after a malfunction:
DAC clocking signal: 500/600 MHz
If the problem occurs, the only solution is to temporarily cut off power to the DAC chip. Simply uploading the configuration, turning PD mode on and off, uploading the FPGA configuration again, does not resume the DAC operation.