HX711 Load Cell Amplifier

The HX711 is a dedicated 24-bit delta-sigma analog-to-digital converter (ADC) amplifier module purpose-built for interfacing Wheatstone bridge load cells and strain gauges with microcontrollers. Without a signal amplifier like the HX711, the millivolt-level output signals from a load cell are far too weak for a standard microcontroller ADC to read accurately — this module solves that problem cleanly and affordably, making it the most widely adopted load cell interface in the maker and electronics community.

The HX711 breakout board features two selectable differential input channels, an on-chip programmable gain amplifier (PGA) with gains of 32, 64, and 128, and a simple two-wire serial interface using only a Clock (SCK) and Data (DT) pin — compatible with virtually any GPIO-capable microcontroller including Arduino, ESP32, Raspberry Pi, PIC, and STM32. Output data rates of 10SPS or 80SPS are hardware selectable via the RATE pin, balancing measurement speed against noise performance. An on-chip oscillator eliminates the need for any external components, and simultaneous 50Hz and 60Hz supply noise rejection keeps readings stable even in electrically noisy environments.

With an operating current under 1.5mA, a power-down current below 1µA, and an on-chip power-on-reset circuit, the HX711 is equally at home in battery-powered portable scales, industrial weighing platforms, liquid dispensers, and force measurement systems.

Specification:

• IC : HX711
• ADC Resolution : 24-bit delta-sigma
• Input Channels : 2 differential (Channel A & B)
• Programmable Gain : 32 (Ch. B) / 64 & 128 (Ch. A)
• Output Data Rate : 10 SPS / 80 SPS (RATE pin selectable)
• Operating Voltage : 2.7V – 5V DC
• Operating Current : < 1.5mA
• Power-Down Current : < 1µA
• Supply Noise Rejection : 50Hz & 60Hz simultaneous
• Interface : 2-wire serial (SCK + DT)
• On-chip Oscillator : Yes (no external crystal required)
• On-chip Power-On Reset : Yes
• Operating Temperature : -20°C to +85°C
• Compatible Load Cells : Any 4-wire Wheatstone bridge load cell
• Compatible Boards : Arduino, ESP32, Raspberry Pi, STM32, PIC
• Package Includes : 1 × HX711 Load Cell Amplifier Module