SDG #127 Testing out a 15 kV Inverter for a Simple ESD Simulator

Electrostatic discharge testing is normally the preserve of expensive certified ESD guns, so this episode looks at whether a low cost high voltage inverter module, sold on the usual marketplaces as a 15 kV generator, can be pressed into service as the heart of a homebrew ESD simulator. The starting point is characterising the module itself: what supply voltage and current it actually draws, what output it produces once loaded, and how far the claimed 15 kV figure survives contact with reality rather than a no load spec sheet number.

The practical problem with these small inverters is that they are designed for arc lighters and ioniser duty, not for charging a defined capacitance to a defined voltage. That matters because an ESD event of the type described in IEC 61000-4-2 is a specific waveform, driven by a storage capacitor in the region of 150 pF discharged through a series resistance of around 330 ohms into the device under test. Measuring the output is awkward too, since a standard multimeter or scope probe will not survive kilovolts and will load the source enough to skew the reading, so a suitably rated high voltage divider approach is needed before any of the numbers mean much.

For anyone considering the same build, the takeaway is about expectations. A cheap inverter plus a carefully chosen capacitor and resistor network can give you a repeatable, roughly controlled zap that is genuinely useful for shaking out latch ups, resets and ESD sensitive input pins during development. It will not give you compliance grade results, but as a workshop tool for provoking faults before a product goes to a test house, the cost to benefit ratio is hard to argue with. Safety discipline around stored charge and creepage distances is non negotiable.