Why a 3A gate driver with 35kV/µs CMTI matters for inverter designs
The FOD8316R2 is an optocoupler-based gate driver from onsemi that delivers 3A peak output current with 4243Vrms isolation — enough to drive medium-power IGBTs and MOSFETs directly without a booster stage. The 35kV/µs common-mode transient immunity means it stays latched to the correct output state when the inverter half-bridge switches at high dv/dt, a common failure point in motor drives and UPS systems. Rise and fall times are both 34ns typical, which keeps dead-time margins tight and reduces switching losses in the power stage. The 500ns max propagation delay is symmetric between high and low edges, so the pulse width distortion stays under 300ns — important for maintaining accurate PWM duty cycles across the isolation barrier.
Supply rail and output drive capability
The output side operates from 15V to 30V, covering the typical gate drive voltages for IGBTs (15V on, -5V to -10V off) and MOSFETs (10V to 20V). The high and low output currents are both rated at 2.5A, so the driver can source and sink symmetrical gate charge — no need for a separate pull-down resistor to discharge the gate quickly. Single-channel configuration means one device per gate, which simplifies layout for three-phase inverters: three FOD8316R2s cover the six-switch bridge.