SparkFun
SparkFun OpenScale
The SparkFun OpenScale is an open-source weight measurement board designed for load cells. Simply connect a four-wire or five-wire load cell of any capacity,...
The SparkFun OpenScale is an open-source weight measurement board designed for load cells. Simply connect a four-wire or five-wire load cell of any capacity, plug into USB, open a serial terminal at 9,600 bps, and you'll immediately see mass readings. A built-in serial menu lets you configure calibration values, sample rate, timestamps, and units of precision.
Designed for static and continuous weighing applications — such as monitoring systems, conveyor belts, and long-term data logging — the OpenScale can operate unattended for months. An on-board TMP102 temperature sensor records ambient temperature alongside weight data.
Key Features
- HX711 24-Bit ADC – High-resolution load cell amplifier for accurate weight measurement
- ATmega328P Microcontroller – Handles serial communication and configuration
- TMP102 Temperature Sensor – Records ambient temperature alongside weight data
- FT231 USB-to-Serial – Mini-USB connection for data output
- Configurable Baud Rate – 1,200 to 1,000,000 bps (default 9,600 bps 8-N-1)
- Serial Configuration Menu – Set calibration, sample rate, timestamps, and precision via terminal
- Multi-Cell Support – Works with single load cells or four sensors in Wheatstone bridge configuration
Ideal For
- DIY weigh scales and measurement systems
- Long-term unattended weight monitoring
- Industrial and conveyor belt weighing
- Data logging with OpenLog or similar serial loggers
Package Contents
- 1× SparkFun OpenScale Board
Resources
Jargon buster
Plain-language definitions for the technical terms used above.
- ADC
- An analogue-to-digital converter reads a changing voltage and turns it into a number the microcontroller can use. It matters when connecting analogue sensors such as light, sound, or variable-resistor sensors.
- ATmega328P
- An 8-bit microcontroller chip used on many Arduino Uno-compatible boards. Knowing the controller uses an ATmega328P helps you understand its memory, speed, pin compatibility, and the Arduino sketches it can run.
- baud
- Baud is the signalling rate of a serial connection, often used as the speed setting for UART communication. Matching the baud rate matters because both connected devices must use the same setting for readable data.
- microcontroller
- A microcontroller is a small computer on a chip that runs your program and controls connected inputs and outputs. For this product, it is the part that reads buttons and sensors, drives the display and speaker, and communicates over Bluetooth.
Find this product in
Brands
Sensors & Input
SparkFun OpenScale Schematic
Schematic · 77.9 KB · Click any page to view full size
HX711 Load Cell Amplifier Datasheet
Datasheet · 263.2 KB · Click any page to view full size
TMP102 Temperature Sensor Datasheet
Datasheet · 1.1 MB · Click any page to view full size
Supplier page — sparkfun.com
Supplier Description · 1.1 MB · Click any page to view full size
Resources & Downloads
Guides, code examples, and more
SparkFun OpenScale Eagle Files
Schematic · ZIP · 176.8 KB
Eagle design files for the SparkFun OpenScale PCB.
SparkFun OpenScale Arduino Library
Example Code · ZIP · 14.2 KB
Arduino library and example code for interfacing with OpenScale.
SparkFun OpenScale Particle Sketch
Example Code · ZIP · 3.7 KB
Example Particle sketch for using the SparkFun OpenScale.
Related Tutorials
Free guides on learn.littlebird.com.au
