HiLetgo ADS1256 5V 8 Channel 24 Bit ADC Data Acquisition Board Module User Manual

1. Introduction

The HiLetgo ADS1256 module is a high-precision 24-bit Analog-to-Digital Converter (ADC) data acquisition board. It integrates the TI ADS1256IDB chip and a 2.5V datum voltage source, designed for applications requiring accurate analog voltage measurements.

This module communicates via the SPI interface protocol and offers data output rates up to 30ksps. It supports both single-ended and differential input configurations, making it versatile for various data acquisition tasks.

Key Features:

• On-board High precision TI ADS1256IDB ADC chip.
• On-board ADR03 2.5V datum voltage source chip.
• Data output rates up to 30ksps, with nonlinearity as low as ±0.0010%.
• Configurable for 8 single-ended inputs or 4 differential inputs.
• Suitable for measuring analog voltages within 3V.

2. Product Overview

The ADS1256 module is a compact board designed for precise analog data collection. Understanding its physical layout and pin assignments is crucial for proper integration and operation.

Figure 2.1: Top view of the HiLetgo ADS1256 module, showing the main components and layout.

2.1. Interface Pinout

The module features several pins for power, communication, and analog input. Refer to the diagram below for pin identification.

Figure 2.2: Bottom view of the HiLetgo ADS1256 module, illustrating the labeled interface pins.

• 5V, GND: Power input pins for a 5V DC supply.
• SCLK, DIN, DOUT, CS: SPI communication interface pins.
  • SCLK: Serial Clock
  • DIN: Data In (MOSI)
  • DOUT: Data Out (MISO)
  • CS: Chip Select (Active low)
• DRDY: ADS1256 Data Ready output pin (Active low level). Indicates when new conversion data is available.
• PDWN: ADS1256 Sync / Power Down input pin (Active low level). Used for synchronization or to power down the device.
• AIN0-AIN7: Analog voltage input pins. These can be configured as either 8 single-ended inputs or 4 differential inputs.

Important Note: The measured voltage must share a common ground with the module. Due to the ADS1256's 5V operating voltage and the requirement for the measured voltage to be at least 2V below the supply voltage, this module is suitable for measuring analog voltages within 3V.

3. Setup and Operation

This section provides a basic example for connecting and operating the ADS1256 module with a microcontroller. The module supports various microcontrollers, and reference programs are often available.

3.1. Basic Connection Example (STC89C52 Microcontroller)

This example demonstrates connecting the ADS1256 module to an STC89C52 microcontroller with a 1602 LCD for displaying voltage values.

1. Power Supply: Connect the 5V and GND pins of the ADS1256 module to a DC 5V power supply.
2. SPI Communication: Connect the SPI pins of the ADS1256 module to the microcontroller as follows:
   • SCLK to Microcontroller P1.2
   • DIN to Microcontroller P1.3
   • DOUT to Microcontroller P1.4
   • DRDY to Microcontroller P1.5
   • CS to Microcontroller P1.6
3. Analog Inputs: For testing, connect the analog input pins as follows:
   • AIN0 to 2.5V
   • AIN1 to 2.5V
   • AIN2 to 2.5V
   • AIN3 to 2.5V

   Ensure the measured voltage source shares a common ground with the ADS1256 module.
4. Display: Connect a 1602 LCD to the microcontroller for displaying the measured values.

Upon successful setup, the 1602 LCD will display four sets of voltage values. For the given test connections (AIN0-AIN3 all connected to 2.5V):

• The 1st set will show the single-ended input voltage of AIN0 (expected: 2.5V).
• The 2nd set will show the single-ended input voltage of AIN1 (expected: 2.5V).
• The 3rd set will show the differential input voltage of AIN2-AIN3 (expected: 0V, as both are 2.5V).
• The 4th set will show the single-ended input voltage of AIN3 (expected: 2.5V).

Reference programs for STC15W and STM32 microcontrollers with 8-channel serial display are also available.

4. Maintenance

The HiLetgo ADS1256 module is designed for durability and requires minimal maintenance. To ensure optimal performance and longevity:

• Keep the module clean and free from dust and debris. Use a soft, dry brush or compressed air for cleaning.
• Avoid exposing the module to extreme temperatures, humidity, or corrosive environments.
• Handle the board with care to prevent physical damage to components or solder joints.
• Ensure proper grounding and power supply to prevent electrical damage.

5. Troubleshooting

If you encounter issues with your ADS1256 module, consider the following troubleshooting steps:

• No Power/Indicator Lights: Verify that the 5V power supply is correctly connected and providing the specified voltage. Check for loose connections.
• Incorrect Readings:
  • Ensure the measured voltage is within the 3V operating range of the module.
  • Confirm that the ground of the measured voltage source is common with the module's ground.
  • Check SPI communication lines (SCLK, DIN, DOUT, CS) for proper connections and signal integrity.
  • Verify your microcontroller code for correct configuration of the ADS1256 (e.g., single-ended vs. differential, gain settings).
  • Inspect for any short circuits or damaged components on the board.
• Communication Errors: Check the SPI wiring and ensure the microcontroller's SPI settings (clock polarity, phase) match the ADS1256 requirements. Verify the DRDY pin's status.
• Software Issues: If using a library, ensure it is correctly installed and configured for your specific microcontroller and the ADS1256 module. Consult the library's documentation or community forums.

For persistent issues, refer to the ADS1256 datasheet or contact HiLetgo technical support.

6. Specifications

7. Package Contents

The standard package for the HiLetgo ADS1256 module includes:

• 1x HiLetgo ADS1256 24 Bit 8 Channel ADC AD Module

Figure 7.1: Example packaging for the HiLetgo ADS1256 module.

8. Support and Warranty

8.1. Technical Support

For technical assistance, questions, or any issues encountered with your HiLetgo ADS1256 module, please contact HiLetgo customer support.

Email: support@hiletgo.com

Please provide your product model and a detailed description of the issue when contacting support to facilitate a quicker resolution.

8.2. Warranty Information

HiLetgo products are typically covered by a limited warranty against defects in materials and workmanship. Specific warranty terms and duration may vary. Please retain your proof of purchase for warranty claims.

For detailed warranty information, please refer to the official HiLetgo website or contact customer support.