# ADS1256 24-bit data acquisition module with STM32F103C8T6, 8 channels, RS232, UART

- Page: https://sigmanortec.ro/en/ads1256-24-bit-data-acquisition-module-with-stm32f103c8t6-8-channels-rs232-uart
- Price: 205.17 RON
- Availability: In stock; 1-2 zile
- Reference: 88274 · EAN: 5942921240330
- Category: Mechatronics and IoT > Sensors and Modules > ADC and DAC Modules
- Specifications: Microcontroller: STM32F103C8T6; Communication interface: RS232, UART; Number of channels: 8; ADC resolution: 24 bit
- Package (shipping data): 0.045 kg
- Updated: 2026-10-01
- Shop: [Sigmanortec.ro](https://sigmanortec.ro/en/llms.txt)
- Prices: RON, VAT included; prices and stock as of 2026-10-22 03:48 (Europe/Bucharest)

## Description

Compact solution for precise measurements of weak analog signals from sensors, load cells or Wheatstone bridges, with 24-bit ADS1256 ADC, up to 30 kSPS and PGA 1-64 for amplification, 8 channels configurable as single-ended or differential, fast data transmission via RS232 DB9 or UART to PC, PLC or development boards, integrated stable 2.5 V reference.
The high-precision data acquisition module combines the ADS1256 analog-to-digital converter and the STM32F103C8T6 microcontroller on the same board, providing a complete solution for reading weak analog signals from sensors, load cells, thermocouples, Wheatstone bridges, or precision voltage sources. The converted data is sent to a computer or another development board via RS232 or UART, making the module suitable for laboratory applications, industrial monitoring, weighing, testing, and precision measurement projects.
The ADS1256 converter is a 24-bit delta-sigma type, with a sampling rate of up to 30 kSPS and an integrated programmable gain amplifier (PGA), adjustable from 1 to 64, which amplifies low-level signals before conversion. The converter is clocked by a dedicated 7.68 MHz crystal, and the on-board 2.5 V reference source ensures measurement stability. The board provides 8 analog input channels, marked I0 - I7, each with a nearby G ground pin, usable as single-ended inputs or configured as up to 4 differential pairs. The input filter includes 0603 footprints for attenuation resistors (not installed by default), allowing dividers to be built for measuring higher voltages.
The STM32F103C8T6 microcontroller manages the converter and external communication. Main features include the DB9 connector for RS232 implemented with the MAX3232 circuit, the UART connector (TX, RX, G) for USB-TTL adapters, the 20-pin JTAG interface compatible with J-Link V8 and J-Link V9, two GPIO pin headers for the STM32 (P8 and P9), reset button, BOOT0 and BOOT1 jumpers for selecting the boot mode, power LED, and a test potentiometer that can be connected via jumper to input I0 for quick functional checks. Power is supplied at 6 - 9 VDC through the screw terminal block or directly at 5 VDC through the +5V and GND pins.
Through the UART interface, the module is compatible with Arduino, ESP32, STM32, Raspberry Pi, and other platforms that have a serial port, and through RS232 it can be connected directly to computers, PLCs, and industrial equipment with a classic serial port.
Specifications:
ADC chip: ADS1256
Microcontroller: STM32F103C8T6
Converter type: Delta-sigma
Resolution: 24 bits
Analog input channels: 8 single-ended (I0 - I7) or 4 differential
Amplifier: Integrated PGA, gain 1 - 64
Sampling rate: up to 30 kSPS
ADC clock: 7.68 MHz crystal
Reference voltage: 2.5 V
Supply voltage: 6 - 9 VDC (P1 terminal) or 5 VDC (+5V / GND pins)
Communication interfaces: RS232 (DB9, MAX3232), UART (TX / RX / G)
Programming / debugging: 20-pin JTAG (J-Link V8 / V9), UART bootloader
Startup control: BOOT0 and BOOT1 jumpers, Reset button
Extras: Test potentiometer on I0, power LED, 0603 attenuation footprints
Dimensions: 59 x 87 mm
Layout:
1. Power terminal: Power input with voltage between 6 and 9 VDC.
2. 5 V power input
3. STM32F103C8T6 GPIO pins
4. Main microcontroller: original STM32F103C8T6.
5. 2.5 V reference source
6. Adjustable potentiometer: Allows adjustment of the output voltage, connected to AIN0 / I0 input
7. 8-channel analog inputs: The I0-I7 channels are used for analog signal acquisition. The G pin is the ground (GND) for the analog signals.
8. Input filter and attenuation resistors: Circuit intended for filtering and attenuating the input signal. In the default configuration, the attenuation resistors are not installed. The component footprint is 0603.
9. ADS1256IDB acquisition circuit: High-precision analog-to-digital converter (ADC), original component
10. Indicator LED
11. JTAG interface: Compatible with J-Link V8 and J-Link V9 programmers and debuggers
12. Mounting holes
13. STM32F103C8T6 RESET button: Button for resetting the microcontroller
14. USB-TTL interface: Connector for serial communication with the computer, providing access to the microcontroller’s TX, RX and GND signals
15. MAX3232 serial circuit: Integrated circuit for RS-232 serial communication
16. DB9 serial connector: Connector for the serial interface
17. Potentiometer connection control to I0 / AIN0: Allows connecting or disconnecting the voltage provided by the adjustable potentiometer to I0 / AIN0 input. When the connection is open, the I0 pin remains unconnected, and when connected, I0 measures the voltage set by the potentiometer.
18. BOOT0 and BOOT1 jumpers for STM32: Allow selection of the STM32 microcontroller boot mode
Pinout:
Connector
Pin
Function
P1 Power terminal
+
6–9 VDC supply
P1 Power terminal
−
GND
J2 Power header
+5V
Direct 5 VDC supply
J2 Power header
GND
Ground
P5 Analog inputs
I0
Analog channel 0 (AIN0, can be connected to the potentiometer)
P5 Analog inputs
I1–I7
Analog channels 1–7 (AIN1–AIN7)
P5 Analog inputs
G
Signal ground (one G pin next to each channel)
P4 UART (USB-TTL)
TX
STM32 data transmission (to adapter RX)
P4 UART (USB-TTL)
RX
STM32 data reception (to adapter TX)
P4 UART (USB-TTL)
G
Ground
J1 DB9
−
RS232 via MAX3232
J3 Jumper
−
Connects potentiometer R15 to I0
P8/P9
−
STM32F103C8T6 GPIO pins
JTAG
20 pins
Programming/debugging with J-Link V8/V9
BOOT0
BOOT1
STM32 boot mode
0
X
Run program from Flash memory (normal operation)
1
0
System bootloader (programming via UART)
1
Boot from SRAM
Usage:
Connect the signals to be measured to inputs I0 - I7, with the ground of each signal to the adjacent G pin of the channel, and for differential measurements use channel pairs (for example I0 - I1).
Do not apply negative voltages relative to G or above 5 V to the analog inputs, and for higher voltages install attenuation resistors in the dedicated 0603 footprints.
For a quick test, install jumper J3 to connect potentiometer R15 to I0 and rotate the potentiometer to observe the variation of the measured value.
Remove jumper J3 when using input I0 for an external signal.
Power the board at 6 - 9 VDC through terminal P1 or at 5 VDC through the +5V and GND pins of J2, observing polarity and using only one power source, and the power LED will light up.
Connect the board to the computer through the DB9 connector with an RS232 cable or through connector P4 with a 3.3 V USB-TTL adapter (board TX to adapter RX, board RX to adapter TX, G to GND).
To connect to Arduino, ESP32, or other boards, use connector P4 with a common ground, and for boards with 5 V logic a logic level converter is recommended.
For normal operation, leave BOOT0 at 0 and press the RESET button.
To upload your own firmware via UART, set BOOT0 to 1 and BOOT1 to 0, press RESET, program the microcontroller with STM32CubeProgrammer, then set BOOT0 back to 0 and reset the board.
Alternatively, programming and debugging can be done through the JTAG interface with a J-Link V8 or V9 programmer.
For stable results, use short, shielded cables for weak signals and avoid noise sources near the board.
Dimensions diagram: