High-Precision AD/DA Expansion Board for Raspberry Pi

There's no Analog-to-Digital/Digital-to-Analog (AD/DA) function on the Raspberry Pi GPIO interface, which can restrict the use of certain components in your project. This High-Precision AD/DA Board allows you to add high-precision AD/DA functions to your Raspberry Pi! Note: Sensors pictured but not included! Features

* Standard Raspberry Pi 40-pin GPIO extension header

* Onboard ADS1256, 8-channel 24-bit high-precision ADC (4ch differential input), 30ksps sampling rate

* Onboard DAC8552, 2-ch 16-bit high-precision DAC

* Onboard input interface via pin headers, for connecting analogue signal

* the pinout is compatible with Waveshare sensor interface standard, easy to connect various analogue sensor modules

* Onboard input/output interface via screw terminals, for connecting analogue/digital signal

* Features AD/DA detect circuit, easy for signal demonstration

Resources

* Product Wiki and guide

What's onboard?

* Raspberry Pi GPIO interface: for connecting with the Pi

* AD/DA input/output : screw terminals

* AD input: pin headers, the pinout is compatible with Waveshare sensor interface standard, easy to connect various analogue sensor modules

* 7.68M crystal

* LM285-2.5: provides the reference voltage for the ADC chip

* Photoresistor

* LED output indicator

* 10K potentiometer

* DAC8552 : 16bit high-precision DAC, 2ch

* Power indicator

* ADS1256 : 24bit high-precision ADC, 8ch (4ch differential input)

* ADC testing jumper

* DAC testing jumper

* Power selection jumper

* ADC reference ground configuration: when AD single inputted, the AINCOM is reference terminal, can be connected to GND or external reference voltage

Interface

PIN SYMBOL DESCRIPTION

1, 17 3.3V Power supply (3.3V)

2, 4 5V Power supply (5V)

3, 5, 7, 8, 10, 18, 22, 24, 26, 27, 28, 29, 32, 36, 38, 40 NC NC

6, 9, 14, 20, 25, 30, 34, 39 GND Ground

11 DRDY ADS1256 data ready output, low active

12 RESET ADS1256 reset input

13 PDWN ADS1256 sync/power off input, low active

15 CS0 ADS1256 chip select, low active

16 CS1 DAC8552 chip select, low active

19 DIN SPI data input

21 DOUT SPI data output

23 SCK SPI clock

31, 33, 35, 37 GPIO extend to sensor interface