Hardware Podcasts

Measuring Current with Matt Liberty

The Amp Hour · 25 Jan 2021 · 1h 20m · Episode 527

What this episode covers

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.

Most relevant to

early-stage companies

Topics

Mentioned

Companies
Keithley, Keysight, Nordic, DigiKey
Products
Joulescope, Power Profiler Kit 2, Salae Logic
Chips
nRF52, Lattice iCE40

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