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

HX711 24-Bit Load Cell Amplifier
The HX711 acts as the bridge between the physical world of weight and the digital world of your microcontroller. It is specifically designed to interface with Wheatstone Bridge sensors (load cells), which are the standard components found inside digital bathroom and kitchen scales.

 
Key Features & Capabilities:
• 24-Bit Precision: This offers an incredible level of detail. To put that in perspective, a standard Arduino has a 10-bit ADC (1,024 levels), while the HX711 has over 16 million levels of resolution.
• Dual-Channel Input: It features two channels (A and B). Channel A is typically used for the main scale, while Channel B can be used for a second sensor or system monitoring.
• Programmable Gain: It includes an internal Low-Noise Amplifier (LNA) with a gain of 128x. This boosts the tiny electrical signal from the load cell so it can be accurately digitized without losing data to electrical noise.
• No Dual Power Supply Needed: It operates on a simple 2.7V to 5.5V range, meaning it can be powered directly from your microcontroller without needing specialized power circuitry.

 
Working Principle:
Load cells contain strain gauges that change resistance when stretched or compressed. The HX711 measures the resulting voltage difference, amplifies it, and sends the data to your board via a two-wire serial interface (Clock and Data).
Technical Specifications:
• Differential Input Voltage: ±40mV (at 128x gain).
• Data Rate: Selectable 10SPS (samples per second) or 80SPS.
o Tip: Use 10SPS for maximum stability/accuracy and 80SPS for fast-moving applications.
• Current Consumption: < 1.5mA during normal operation (ideal for battery-powered IoT scales).

 
Best For:
The HX711 is the go-to module for digital kitchen scales, industrial weighing systems, smart beehives (to monitor honey production), and automated inventory bins.