ADS1256 24bit ADC Module

ADS1256 24bit 8channel ADC Module

ADS1256 from Texas Instruments is a 24-bit, 30 KSPS 8 channel Delta Sigma ADC. This modules provides a simple way to interface the ADS1256 IC to various Micro-controllers, Arduino and even to Raspberry Pi.

ADS1256 function and characteristics

• On-board high precision TI  ADS1256IDB  ADC chips

• On-board ADR03 2.5V datum voltage source chips

• Data output rates up to 30ksps, nonlinearity is low to ±0.0010％

• The module can be configured as either 8 single-ended inputs or 4 differential inputs

• ADS1256 module is suitable for measuring analog voltage within 3V

• Module operating voltage is 5V

Interface description

• 5V、GND：5V power input
  
• SCLK, DIN, DOUT, CS：SPI communication Interface
  
• DRDY：ADS1256 data be ready output (Active low level)
  
• PDWN：ADS1256 Sync / Turn off the power input (Active low level)
  
• AIN0-AIN7：Analog voltage input, it can be configured as either 8 single-ended inputs or 4 differential inputs,(The measured voltage should be shared with the module)
  

Precautions

Because the voltage of ADS1256 is 5V,and The measured voltage should be 2V below the supply voltage, so The module is only suitable for measuring analog voltages within 3V.

Testing Methods

Module provides STC15W and STM32 microcontroller 8-channel serial display reference program and STC89C52 single-chip 4-channel 1602LCD display reference program, the STC89C52 single-chip + 1602 LCD LCD test method is as follows:

5V、GND connect to DC 5V power supply, SCLK、DIN、DOUT、DRDY、CS connect to Single-chip P1.2, P1.3, P1.4, P1.5, P1.6 respectively, AIN0、AIN1、AIN2、AIN3 connect to 2.5V、2.5V、2.5V、2.5V respectively (The measured voltage should be in common with the ADS1256), then 1602 LCD will shows these four sets of voltage values, in which, the 1st ,2nd ,4th sets are single-ended input voltage value of AIN0、AIN1、AIN3, and the 3rd set is the difference of  AIN2-AIN3, the voltage values of these four sets are 2.5V、2.5V、0V、2.5V

Related Links

• ADS1256 Basic Arduino Library
• Arduino Forum for ADS1256 Module