Adafruit INA228 85V 20-bit I2C Power Monitor Breakout

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.

breakout

A breakout board carries a small or fine-pitched component and brings its connections out to standard, breadboard- and header-friendly pins. Describing a part as a breakout means it can be wired into a project without soldering directly to the component's tiny contacts.

CircuitPython

A beginner-friendly version of Python designed to run directly on microcontroller boards. If a product supports CircuitPython, you can often program it by copying code files onto the board rather than setting up a more complex toolchain.

common-mode voltage

The voltage level that both measurement inputs sit at relative to ground while the sensor measures the small difference between them. A high common-mode rating means the board can monitor current in higher-voltage circuits without the measurement chip being damaged.

DC

DC means direct current, where electricity flows in one constant direction, as supplied by batteries, USB ports and many plug-pack power supplies. When a product specifies DC, it runs from a DC supply rather than mains AC, so you need to provide the correct voltage and polarity.

high-side measurement

Measuring current on the positive supply side of a load, before the power reaches the device being measured. This matters because it lets you monitor a circuit without disturbing its ground connection, which is often safer and more accurate for shared-ground projects.

I2C

I2C is a two-wire communication bus used by many sensors and small modules. It matters because several I2C devices can share the same two wires, but each device needs a compatible address and your controller must support I2C.

INA228

A power-monitoring chip that measures current, voltage and power in a circuit and reports the readings digitally. The exact chip matters because it sets the measurement range, resolution and communication method for the breakout.

LSB

Least significant bit (LSB) is the lowest-order bit in a binary number, the bit that some serial protocols send first or last. In analogue-to-digital and digital-to-analogue converters, one LSB also means the smallest step the device can resolve, equal to its full-scale range divided by the number of steps.

oversampling

Taking many measurements and combining them to reduce noise and improve the stability of a reading. It matters when you want smoother current or power measurements, though it can make updates slower.

shunt resistor

A very low-value resistor placed in the current path so the board can measure the tiny voltage drop across it and calculate current. Its resistance and tolerance affect the maximum current range, heat produced and accuracy of the readings.

Terminal block

A terminal block is a connector that joins wires together in a neat, removable, or serviceable way, usually clamping each wire under a screw or spring instead of soldering. It makes it easier to connect, change, or service wiring without permanent joints.

Tolerance

Tolerance tells you how far the real resistance value may be from the printed value. A 1% resistor is useful when a circuit needs more predictable behaviour than a looser 5% or 10% part.

VBUS

VBUS is a label for a bus or supply voltage. Most commonly it is the +5V power line carried over USB, though on power-monitoring hardware it instead marks the bus-voltage input being measured, so check which sense applies before connecting power or a measurement point.