The SparkFun Coulomb Counter Breakout - LTC4150 functions as an odometer for electrical current, continuously monitoring and summing the current used by a sensor. It provides a pulse each time a specified amount of amp-hours is consumed, allowing precise tracking of battery usage. The device features headers for connecting a battery or power supply and a six-pin header for microcontroller connections, including Voltage Input, Interrupt, Polarity, Ground, Clear, and Shutdown. Install it between the power source and the circuit to measure all current usage.