High temperature, high reliability isolated gate driver supports high density power converters

November 04, 2011 // By Paul Buckley
CISSOID has launched HADES, which is claimed to be the first isolated gate driver solution designed to drive high temperature power transistors, specifically (but not exclusively) Silicon carbide (SiC) and Gallium nitride (GaN) fast-switching devices.

With HADES, system engineers can develop power converters that are five times smaller and lighter than before, with better efficiency. They will also get power converters able to operate in high temperature ambiance if required. No matter what the ambient temperature is, the life time of the system will be an order of magnitude longer than traditional solutions.
HADES has been designed to drive seamlessly Silicon Carbide (SiC) power transistors, which have low switching losses. HADES can switch them at high frequencies, which means smaller and lighter passive and magnetic components. Furthermore, thanks to its ability to sustain high temperatures, HADES can be located next to the power transistors which reduces parasitic capacitances and inductances, and that further improves the associated losses and delays in the system.
HADES is a reference design and an Evaluation Board delivered with full documentation. It can drive two SiC MOSFET power switches on a DC bus voltage up to 1200 V. The Reference design is scalable up to +/-20 A gate current, while the Evaluation Board features +/-4 A.  A specific board flavour for normally-On JEFTs will also be available, and other types of switching devices (normally-On/Off JFETs, BJTs and IGBTs) can be supported with minor changes.
As an example, HADES operation and performances were demonstrated in a3 kW Buck DC-DC converter, driving SiC MOSFETs, at 175°C ambient and switching at 150 kHz, with rise times of less than 25 ns. In these operating conditions, HADES, which has been designed for high dV/dt immunity (50 kV/µs) and IC junction temperatures up to 225°C, runs with comfortable safety margins.
In terms of efficiency, the combination of HADES with the newest SiC switches in advanced power converter topologies will bring efficiencies in excess of 98%, even at switching frequencies above 100 kHz.
HADES gate driver is the ideal solution for high-power converters such as motor drives, battery chargers and power distribution