HX711 is a precision 24-bit analog-to-digital converter (ADC) designed for weight scales (Load Cells) and industrial control applications to interface directly with a bridge sensor.
Specification
- Differential input voltage: ±40mV (Full-scale differential input voltage is ± 40mV)
- Data accuracy: 24-bit (24-bit A / D converter chip.)
- Refresh frequency: 80 Hz
- Operating Voltage: 5V DC
- Operating current: <10 mA
- Size:38mm*21mm*10mm
Why This Is a 24-Bit ADC (Not a Regular Sensor Board)
The HX711 chip itself is a precision 24-bit ADC with a built-in programmable gain amplifier (32x, 64x, or 128x) and two input channels — it doesn't just read a load cell's signal, it amplifies the tiny voltage difference a load cell produces and converts it straight into a clean digital value. The chip also integrates its own voltage regulator and oscillator, so this module needs very little else around it to work.
Does It Come With a Load Cell?
No — the HX711 is the amplifier/converter board only. It's designed to connect directly to a separate load cell (strain gauge) in a Wheatstone bridge configuration, which is where the actual weight sensing happens. RAM Electronics carries straight-bar load cells in several capacities — 5kg, 20kg, 40kg, 50kg, and 100kg — pick the one matching the maximum weight your project needs to measure.
Using the HX711 with Arduino
The HX711 communicates over a simple 2-wire interface (clock + data), which keeps wiring straightforward on an Arduino UNO or similar microcontroller — no complex protocol or extra components needed to read a weight value. This simplicity is why the HX711 is the standard choice behind most DIY digital scale projects built with Arduino.
Common Uses for This Module
- DIY digital kitchen or postal scales.
- Industrial weight/force monitoring on a production line.
- Load-detection projects — knowing when an object is present or its weight has changed.
- Robotics and automation projects needing simple force feedback.
Frequently Asked Questions
Does the HX711 need a separate load cell to work?
Yes — the HX711 is the amplifier and analog-to-digital converter only; it needs a separate load cell (strain gauge) connected to it to actually sense weight or force.
Can the HX711 work with an Arduino?
Yes — it communicates over a simple 2-wire (clock + data) interface, which is why it's the standard module used in most Arduino-based digital scale projects.
How accurate is the HX711's measurement?
It's a 24-bit ADC with a programmable gain amplifier (up to 128x), giving it very fine resolution on the small voltage signal a load cell produces — accuracy in an actual build also depends on the load cell used and calibration.
What's the maximum reading rate of the HX711?
Per this module's specification, its refresh rate is 80Hz; the HX711 chip itself supports a selectable 10Hz or 80Hz output rate.
Building a digital scale or force-sensing project? Pair the HX711 24-bit ADC module with one of RAM Electronics' load cells and an Arduino for a complete, accurate weighing setup.
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