Other Parts Discussed in Thread: AFE7222, , CDCE72010, AFE7225
I have AFE7225EVM which has AFE7222 analog front end IC on it. I want to test the board without using TSW140x EVM's. I know that the easiest way is to use TSW boards but I need to be sure that my AFE board is working before purchasing th TSW board. I read the datasheet and there is an option to use RX-TX loopback. I have tried to change most of the registers that may be related with loopback but could not manage it.
Here is my test configuration:
The board is powered by 6V Wall Adapter supplied by TI, power jumpers are left as-is and checked that they are correct according to AFE7225EVM User Guide.
1. CDC Aux IN: 24MHz Sine Wave (2Vpp)
2. INA or INB: 1MHz or 2Mhz or 4MHz Sine Wave - 1MHz or 2Mhz or 4MHz Carrier AM/FM Modulated signal (2Vpp and max. 20kHz bandwidth) - Tried all combinations with nearly all settings.
3. IOUTA or IOUTB are connected to Spectrum Analyzer.
4. CDC registers are remain the same, AFE is clocked /3 of Aux (8Mhz), tried to divide it by /1, still no luck.
5. Tried AFE7225_reg.txt and CDCE72010_reg.txt that is supplied with GUI. Just set RX_TX_LBPK and RX_TX_LBPK_SRC at the same time.
6. Tried to reset all the registers and just set RX_TX_LBPK and RX_TX_LBPK_SRC at the same time.
7. Tried to enable CMIX, MIXERs, QMC options on both RX and TX channels.
8. Tried to enable FIFO options on TX channels.
9. Tried to connect Input to A and B channels and forwarded all DACs to same channels.
And also tried another options but still no luck. Could you please explain me that if it is possible to use loopback function in such way or did I misunderstand the whole concept? Or is there anyway to test the AFE7225EVM without TSW boards?
Thanks for your time,