SparkFun Qwiic Scale - NAU7802

The SparkFun Qwiic Scale is a small breakout board for the NAU7802 that allows you to easily read load cells to accurately measure the weight of an object. By connecting the board to your microcontroller you will be able to read the changes in the resistance of a 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. Utilizing the handy Qwiic system, no soldering is required to connect it to the rest of your system. However, SparkFun have still broken out 0.1"-spaced pins in case you prefer to use a breadboard.



By connecting a load cell to the Qwiic Scale you will be able to translate sensor data into something your microcontroller can read. The NAU7802 is an ADC with built in gain and I2C output to amplify and convert the readings from a standard load cell. A load cell is basically a device that translates pressure or force into electrical signals. In most cases this signal is very small and needs to be amplified. There are many popular chips that read the change and amplify it, but the NAU7802 goes one step further and converts everything to a true I2C output (attached to a Qwiic connector).

The board provides a four spring terminal to connect your load cell with no soldering required. In addition to the I2C pins, the board also breaks out an interrupt pin and AVDD to the edge of the board. The differential input signals (plus a second set of input signals) are broken out to the middle of the board, as well.

Product Video

Quick Spec

• Operating Voltage: 3.3V (NAU7802: 2.7V-5.5V)
• 24-bit Dual-Channel Analog to Digital Converter
• Programmable Gain Amplifier
• On-chip temperature sensor
• Simultaneous 50Hz and 60Hz rejection
• Programmable PGA gains from 1 to 128
• Programmable aDC data output rates
• External differential reference voltage range from 0.1V to 5V
• Low Power Consumption and Programmable Power Management Options

Resources

• Product Page
• Schematic
• Hookup Guide
• NAU7802 Datasheet
• Getting Started with Load Cell
• GitHub

Shipping List

• 1 x SparkFun Qwiic Scale - NAU7802