HX711 – Weighing Scale Analog-to-Digital Converter 24-bit

The Load Cell Amplifier and ADC (Analog-to-Digital Converter) Module is a small breakout board for the HX711 IC that allows you to easily read load cells to measure weight. By connecting the module to your microcontroller you will be able to read the changes in the resistance of the load cell and with some calibration you’ll be able to get very accurate weight measurements. This can be handy for creating your own industrial scale, process control, or simple presence detection.

The HX711 uses a two wire interface (Clock and Data) for communication. Any microcontroller’s GPIO pins should work and numerous libraries have been written making it easy to read data from the HX711. The module communicates with the host computer through TTL 232.

Application:
Widely used in aerospace, mechanical, electrical, chemical, construction, medicine and many other fields, used to measure force, pressure, displacement, strain, torque, acceleration.

Features:

• Two selectable differential input channels
• On-chip active low noise PGA with selectable gain of 32, 64 and 128
• On-chip power supply regulator for load-cell and ADC analog power supply
• On-chip oscillator requiring no external component with optional external crystal
• On-chip power-on-reset
• Simple digital control and serial interface: pin-driven controls, no programming needed
• Measurement Resolution: 24 bit

Specification

• Differential input voltage : ±40mV ( Full-scale differential input voltage is ± 40mV )
• Data accuracy : 24 bit ( A/D converter chip )
• Refresh frequency: 80 Hz
• Operating Voltage : 5V DC (2.6V ~ 5.5V)
• Operating current : <10 mA
• Operation supply voltage range: 2.7V ~ 5.5V
• Selectable 10SPS or 80SPS output data rate
• Simultaneous 50 and 60Hz supply rejection
• Operation temperature range: -40 ~ +85℃
• Pin Number: 10 Pin
• Size : 25mm x 16mm

Pinouts:

Analog Side:
E+: Excitation positive
E-: Excitation negative
A-: Channel A Negative Input
A+: Channel A positive Input
B-: Channel B Negative Input
B+: Channel B positive Input

Digital Side:
GND: 0V / Ground Power Connection
DT: Data IO Connection
SCK: Serial Clock Input
VCC: Power Input

HX711 Datasheet