HX711 Dual-Channel 24 Bit Precision A/D Weight Pressure Sensor

The HX711 Weight Pressure Sensor Module is a precision 24-bit analog-to-digital converter (ADC) specifically designed for weigh scales and industrial control applications.

Technical Specifications:

• Operating Voltage: 2.6V – 5.5V (typically 5V for Arduino use)
  
• Current Consumption: < 1.5mA
  
• ADC Resolution: 24-bit
  
• Input Type: Differential analog (from load cell)
  
• Gain: Programmable (Gain = 128 or 64)
  
• Interface: 2-wire (Clock & Data – similar to SPI but custom)
  
• Typical Load Cell: 1–5kg, 10kg, 50kg strain gauge-based cells
  
• Data Rate: 10 Hz or 80 Hz selectable

Pinouts:

Connection with Arduino:

Note: The E+ / E- / A+ / A- pins are for connecting the load cell wires (strain gauge).

Sample code:

Install HX711 Library:
Open Arduino IDE
Go to Sketch → Include Library → Manage Libraries
Search for HX711 by Bogdan Necula or SparkFun and click Install

Code: 
#include "HX711.h"

// HX711 circuit wiring
const int LOADCELL_DOUT_PIN = 3;
const int LOADCELL_SCK_PIN = 2;

HX711 scale;

void setup() {
  Serial.begin(9600);
  Serial.println("HX711 Weight Sensor Test");

  scale.begin(LOADCELL_DOUT_PIN, LOADCELL_SCK_PIN);

  // Optional: Set a known scale factor after calibration
  // scale.set_scale(2280.f); // Replace with your own value
  scale.tare(); // Reset the scale to 0

  Serial.println("Taring... Please wait.");
  delay(2000);
  Serial.println("Ready to weigh!");
}

void loop() {
  Serial.print("Weight (raw value): ");
  Serial.println(scale.get_units(), 2); // Can replace with .get_units() after calibration
  delay(500);
}