Dear engineers:
Hello!
We use four pieces of AWR2243 for cascade design. The working mode of AWR2243 is fixed by resistors. The SOP mode is SOP4, that is, SOP0=1; SOP1=0; SOP2=0; and the VION pin of AWR2243 is set to 1.8V.
We now encounter a problem. When our FPGA controls the AWR2243 through SPI, if the program does not run, SOP0=1 (that is, SOP0 is 1.8V when it is high). If the program runs, SOP0 becomes 1.0V, so As a result, our FPGA cannot operate the AWR2243 through SPI.
We checked that there was no operation to pull it low after SOP0, and also monitored that the 1.8V voltage output by the AWR2243 power supply chip LP876242 also changed to 1.0V. The strange thing is that if our FPGA does not download the program and does not operate the AWR2243, the 1.8V voltage output by the LP876242 is normal. Once the FPGA debugs and runs the program, the 1.8V voltage output by the LP876242 becomes 1.0V.
What could be the reason? Looking forward to reply, thank you.
