Hi all,
What is the purpose of OUTH and OUTL pin? Why they are two separate pins? Is it to drive two separate switches?Please suggest
hi,
Thanks for your question.
It is not to drive seperate devices, it is to drive one IGBT/FET. Internally, the pull-up portion of the driver consists of NMOS (& PMOS for TI's gate driver) that sources current to the IGBT/FET gate, and the pull-down portion has an NMOS that sinks the current from the IGBT/FET gate. The structure is highlighted in the block diagram from the datasheet below.
In ISO5451, you'll notice that there is only ONE pin for output driving , labeled OUT.
In ISO5452, they are separated. This allows better control over turn off and turn-on without using diodes
For example, ISO5451, if you want to use a different resistance value on turn-on vs turn -off, you have to use a diode seperate the paths. The reason you would want to do this, is for example, to have a lower turn-off current and higher turn-on current.
Please see the link below, which explains further why split outputs is important.
Please let me know if you have further questions. If I've answered your question, could you let me know by pressing the green button?
Best
DImitri
