The goal of the soft shutdown function is to prevent high switching over-voltages at the
time the IGBT is turning off in the event of a short circuit, as these could otherwise
destroy the IGBT.
Examples of an IGBT driver with soft shutdown function are Avago Technologies’
HCPL-316J (driver IC), CONCEPT’s 2SD300C17 (driver board) and Infineon’s
2ED300C17-S (driver board).
The soft shutdown principle
Although soft shutdown limits the switching over-voltage when an over-current or
short circuit is turned off, it is still advisable to implement Active Clamping (chapter
as an additional safety stage. Furthermore, should a short circuit occur at the
moment of turning off, the soft shutdown function can no longer be activated and the
IGBTwould turnoff unprotected.
6.8 Logic functions
In addition to the basic functions described so far, the gate driver can take over other
logic functions thatmake it safer to operate power semiconductors. For example, inhalf-
bridge drivers, there is often a need for an interlock for the semiconductors in a half-
bridge. As well, fault logging functions and even temperature measurements are
implemented in IGBT drivers. Some of the most common and useful functions are