Part Number: ADS131A04
M0 = M1 = M2 = IOVDD therefore we expect to be using 32bit device words with Hamming code enabled.
What are the reasons for the device responding with READY (0xFF04) instead of an UNLOCK ACK (0x0655) when sent the UNLOCK command? I notice from other forum posts that this occurs when the device does not recognise commands and implicates bus settings or word length problems but are there any other causes to investigate?
I see 5x 32 bit words sent as command with the first 16 bits == 0x0655 and 5x 32 bit words with the first 16 bits == 0xFF04 instead of 0x0655.
I am running the SPI bus with a slow clock prescaler value of 256 yielding 562.5 kbit/s. I've also tried with faster clocks with the same results.
I measure REFP as 1.22 V approximately - is this expected? I see the datasheet states that the device starts up with the reference set to external which for us is tied to AVSS via 1uF.
