We are having trouble with the AD5270 in a daisy-chain SPI configuration.
We seem to be meeting the SPI timing and signal level specs, but are never able to get an SDO output from the first pot (which is then daisychained to SDI of the second pot).
Attached are SPI plots.
CH1 - /SYNC
CH2 – DIN
CH3 – SCLK
CH4 – SDO
CH4 SDO remains high on subsequent clock cycles (we'd expect it to shift out the previous 16 data bits - independent of the message). Is there a certain command sequence we should be following? Or anything else we may be missing?