What Problem This Class of Device Solves
Isolated gate driver ICs use an isolation structure (magnetic, optical, etc.) to electrically separate the control signal from the power stage — protecting the low-voltage control circuit from high-voltage breakdown while blocking common-mode noise generated by power-stage switching from reaching the control side. Widely used in motor drives, PV inverters, and switching power supplies.
How to Read the Key Parameters
Isolation voltage (Viso): catalog parts come in 3000Vrms and 5000Vrms tiers, corresponding to different safety isolation classes — select according to the system's insulation design requirements, not by operating voltage alone.
CMTI (common-mode transient immunity): catalog parts are uniformly rated at 150kV/µs. This is especially critical in high-dv/dt applications; a higher rating means stronger resistance to false triggering during fast power-stage switching.
Drive current (IOH/IOL): catalog parts span 3.0/6.0A to 12.0/12.0A. Work this back from the driven device's gate charge and target switching speed — too little current lengthens switching-loss time.
Propagation delay: catalog parts are rated 60ns or 90ns. A shorter delay means a faster drive response, but it must still match the system's overall switching-frequency design.
Protection and output features: some parts support split turn-on/turn-off outputs, active short-circuit clamp (ASC), and soft turn-off — select based on the application's need for short-circuit protection and turn-off overshoot suppression.
Three Steps to Select
- Set the Viso tier (3000Vrms/5000Vrms) from the system's safety isolation class.
- Check drive current and propagation delay against the driven power device's gate charge and switching speed.
- Filter for parts with the matching protection features if the application needs short-circuit protection, soft turn-off, or similar.
Common Pitfalls
- Assuming higher isolation voltage is always better — the isolation class must match the safety requirement; over-specifying can add unnecessary cost and package size.
- Overlooking the source/sink asymmetry in drive current — IOH and IOL values often differ, so check both the turn-on and turn-off directions against your needs.
- Conflating functional isolation with reinforced isolation — the two map to different safety classes, and a Viso number alone doesn't tell you which one a system requires.
To filter parts by specific parameter ranges, use the online selection tool on this site; for further technical questions, contact us through the site's support channel.
Related guide: Automotive 2-Channel Isolated Gate Driver Selection Guide