HX711 load cell amplifier - 24-bit A/D converter, 2.6-5.5 V

Product overview

• 24-bit analog-to-digital converter for load cells and force sensors
• Two input channels with switchable gain (channel A, 64x or 128x, channel B, 32x)
• Channel A input range up to ±40 mV or ±20 mV depending on the gain
• Serial two-wire interface for microcontrollers
• Configurable output data rate between 10 Hz and 80 Hz
• Separate pin headers for sensors and control electronics
• Internal voltage regulation and decoupling capacitors already included

Product description

The 24-bit HX711 analog-to-digital converter digitizes the tiny differential signals from Wheatstone bridge sensors. The module receives the voltage signal from a load cell, amplifies it internally, and provides the measurement result as a digital value that can be read by a microcontroller.

Two independently configurable input channels enable flexible measurement setups. Channel A allows a choice between 64x and 128x gain, corresponding to input ranges of ±40 mV or ±20 mV. Channel B operates with a fixed gain of 32x and can be used for a second sensor. The output data rate can be switched between 10 Hz and 80 Hz to adapt the measurement speed to the application.

Communication with the microcontroller requires only two wires. The controller sends clock signals, and the module then returns the 24-bit measurement values serially. The data rate can also be adjusted via the same clock line. Capacitors already soldered onto the board and an internal regulator eliminate the need for external circuitry.

The module can be used wherever small loads or forces need to be measured, for example in electronic scales for weighing food or people, or in industrial load cells. The setup is minimal: connect the load cell, connect four wires to the microcontroller, and you are ready to go.

Operation requires a power supply between 2.6 V and 5.5 V, as well as compatible interface software for the development board being used. Compatibility with Arduino and Raspberry Pi is provided when the respective software libraries are included.

Safety notice

The module is not intended for connection to household appliances or industrial power supplies and may be used exclusively for prototyping, testing, and development purposes. Calibration is required before the first measurement operation. If you have questions about commissioning or the correct connection of load cells and the power supply, consult a qualified electrician.

Scope of delivery

• HX711 - 24-bit A/D load cell amplifier