Measuring Current with Matt Liberty
Matt Liberty, creator of Joulescope, explains the engineering challenges of measuring high dynamic range currents in low-power IoT devices, specifically addressing the difficulty of switching between milliamp active states and microamp sleep states. He details how Joulescope uses a shunt ammeter design with seamless auto-ranging to minimize burden voltage, preventing device brownouts, and leverages Lattice iCE40 FPGAs for precise, sub-microsecond switching. The conversation covers practical applications for optimizing firmware power profiles, debugging leakage currents from components like bypass capacitors, and managing the supply chain and manufacturing processes for a small-batch hardware startup.