I'm facing problem when reading data register. The SPI communication works perfect, all the registers can be write/read. The data register show -1 (which in datasheet indicates that there is a problem in Vref, checked with setting REF_DET bit and reading STATUS register which shows 0x60).
I'm using adc in BIPOLAR MODE, the steps performed to initialize adc are:
- send 0x000A to mode reg.( this sets adc in continuous mode with 16.7 Hz update rate).
- send 0x0030 to conf. reg.( this sets adc in bipolar, Gain 1, reference detect ON, BUFFER ON, Channel to 1 ie AIN1+ and AIN1-.
- send 0x60 to IO reg. to check p1 and p2 are working.
Please advice why is this happening am I giving wrong Vref, but the datasheet show Vref can be in between 0.1-AVdd and for this I can read upto +-AVdd-100mV (BUFF ON). Please see attached image for reference. I'm trying this CKT from a week now, monitoring Vdd mode works gives some integer value and STATUS reg. shows 4 in this case.