If you are feeling the stress and strain of a Wheatstone bridge and you want to quantify it, this handy breakout will do the job, no sweat! The Adafruit HX711 Breakout contains a super-high-resolution 24-Bit differential ADC with extra gain circuitry that makes it perfect for measuring strain gauges / load cells or other sensors that have four wires that are connected in a Wheatstone bridge arrangement.

Each breakout comes with a HX711 ADC chip, plus some support circuitry, and 6 port terminal block that can be used to connect one or two 4-wire sensors. The E- pad connects to ground (often a black wire), the E+ pad connects to the power voltage supplied to the HX711 (often a red wire).

Then A- and A+ pads connect to the differential outputs from the bridge. For example, connecting to a strain gauge these tend to be the white and green wires. If you have a second gauge or voltage you want to measure, you can use the B- and B+ pads. On the A channel, you can select 64x or 128x gain. On the B channel, you have a fixed 32x gain.

This sensor uses a two-wire protocol, similar to SPI. If you want a similar sensor but I2C, check out the NAU7802 breakout we make. We based this design on the excellent Sparkfun HX711 breakout: incorporating their split analog/digital supply and digital supply filtering. We then made a few tweaks: pre-soldered terminal blocks, the second bridge exposed, and a slide switch to change between 10 SPS and 80 SPS rates.