24bit ADC, Analog Devices AD7780

I received samples from Analog Devices, one of them being 24bit A/D
Looking at datasheet, it is pretty simple device with simple SPI compatible communication.

I wired it for non battery operation, by that I mean BPDSW switch was never opened (bridge of load cell always connected, but I don't use it for load cell measurement anyway)
REFIN(+), AVDD, DVDD, FILTER and PDRST were connected to 5v, GND is connected to ground.
There are two options for data transfer (SPI is any other two pins):
SCLK is either pin 12 when connected with SPI, or pin defined in sketch.
DOUT/RDY is either pin 13 when connected with SPI, or pin defined in sketch.

Settings you could change:
GAIN: when low, gain = 128, when high, gain = 1
FILTER: when low, update rate is set to 16.7 Hz, when filter is set high, update rate is set to 10 Hz
PDRST: when low, ADC is powered-down, if set high, ADC is taken out of power-down mode
BPDSW: if you have this ADC battery powered, you can disconnect the measduring bridge (input circuit outside ADC)

The DOUT/RDY pin is dual purpose: it functions as a data ready pin and as a data output pin.
DOUT/RDY goes low when a new data-word is available in the output register.
A 32-bit word is placed on the DOUT/RDY pin when sufficient SCLK pulses are applied.
This word consists of a 24-bit conversion result and eight status bits.

Non-SPI sketch uses all 32bits and last 8 are used to see if data is valid.
while(statusBits ^ B01001101) here is where you check for that. In my case you compare it to B01001101.

Arduino IDE sketch non-SPI

Arduino IDE sketch SPI

Arduino IDE sketch SPI alternative

AD7780 visits:

Application Note on bridging audio amplifiers

A discussion on bridging audio amplifier circuits like LM3886. Includes a schematic to drive a matched pair of amplifiers in a bridged configuration, power supply considerations for LM3886 and TDA1514 power amplifier circuits-especially in bridged pairs.

Application Note on parallel-bridging LM3886 audio amplifiers

How to make it loud - real loud. (230 watts rms into 8 ohms without clipping from 4 ICs. How to match LM3886s for parallel operation, then bridge the matched parallel banks. If you are not familiar with bridging amplifiers (BTL configuration), read the Application Note on bridging listed left in article Application Note on bridging audio amplifiers.

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