Highly integrated gate driver photocoupler enhances safety when switching SiC MOSFETs

Toshiba Electronics Europe GmbH has released a gate driver photocoupler ideal for driving SiC MOSFETs in industrial equipment like industrial inverters, UPS, and PV inverters, which experience harsh thermal environments. The TLP5814H is a highly integrated gate driver featuring a built-in active Miller clamp circuit that helps enhance system safety and lower overall solution size by minimising the extra external components needed.

The device's integrated active Miller clamp circuit has a channel resistance of 0.69Ω (typ.) and a peak clamp sink current rating of 6.8A. These features assist to prevent the self-turn-on phenomenon associated with some power devices like SiC MOSFETs and IGBTs which are highly sensitive to changes in gate voltage. The integrated Miller clamp in the device lowers system cost, size and complexity by mitigating designers' need to include an additional negative power supply and implement an external active Miller Clamp circuit.

This gate driver photocoupler can deliver a maximum peak output current of +6.8/-4.8A with rail-to-rail output, which helps to enhance system switching performance while ensuring stable operation. An internal Faraday shield ensures common-mode transient immunity of ±70kV/µs (min).

The device can operate reliably in temperatures from -40C to 125C due to the enhanced optical output of the infrared LED on the input side and an optimised high-gain, high-speed light-detecting photodiode array, which assists in improving optical coupling efficiency.

To improve board layout flexibility, the TLP5814H is provided in a small SO8L package measuring only 5.85mm × 10mm × 2.1mm. Also, it has a minimum creepage distance of 8mm, making it ideal for use in applications needing high insulation performance.