Other Parts Discussed in Thread: AFE7444
I have read through all the user manuals and application notes for the AFE7444EVM to place it in Rx-Tx loopback mode. I found the attached configuration file which I found by searching other threads on this same topic. I have my signal source set to 1800 MHz @ -11 dBm. This is attached to A_IN1. I have my spectrum analyzer set to 1800 MHz with 50 MHz bandwidth attached to IOUTA.
I power up the AFE7444EVM by itself. It is not attached to the FMC carrier. I launch the AFE7444EVM GUI and follow all the steps prescribed in application note SLAA871 (see attached). I use the attached configuration file to program the registers in the low-level tab. I then turn on the RF generator and check for IOUTA output but only see what looks like a leakage spur which is -90 dBm down.
I tried different inputs and outputs with the same result. I also note that the AFE7444EVM is only pulling about 1 amp of current. The loopback video shows the AFE7444EVM attached to the FMC carrier and it is pulling over 4 amps. Assuming the power to the AFE7444EVM is not sourcing the FMC carrier in the video, it appears there is something not turning on after configuration.
I have also checked register 0x7E and it it is set for 0x1F which is consistent with mode 4 setting prescribed in the SLAA871 application note. I also checked jumper JP9 and it is set in the 2-3 position. I also looked at other registers set by the attached config file in the low-level tab and they are consistent with the file.
I have exhausted all ideas at this point and need some help.
Regards,
RickAFE74xx as a single-chip wideband repeater using loopback mode_slaa871.pdf2350.AFE74xx_RX_to_TX_LoopBack_pass.cfg