We try to connect AD9361 to STM-µC via adapter-board. Unfortunately µC is running with 3.3V Vcc and AD9361 abs. max. is 2.5V (running at 1.8V @ FMCOMMS-3). That's the reason why we are using level-shifter (3 x TI TxB0108). This works fine for SPI and all unidirectional signals from µC to AD9361. We have lot's of trouble with bidirectional signals (12-bit data port) and all unidirectional signals from AD9361 to µC. Do we need to implement pullup-resistors at AD9361 side for these signals? Unfortunately I couldn't find any information about CMOS-I/O-Circuitry of AD9361. Having this information would be very helpful.
Thanks for your help in advance.