TL783 for ISO 7637?

Paul Toffolo

Other Parts Discussed in Thread: TL750L, TL783

I am looking for a solution that will pass ISO7637. I'm hoping some of you have experience with designing lin regs to pass transient testing.

Right now I see three options:

1) TL750L, which is rated 60V load dump and -50V transient. Max current 150mA is not enough.

2) Linear Technology LT4356 "Surge Stopper". Only current limit is the size of external pass FET. Substantially greater cost, board space and design time will be needed.

3) TL783: rated 125V, 700 mA - if a diode is placed in the input series current path, followed by a bi-directional TVS at the TL783 input, is that likely sufficient to pass ISO7637, or is this too minimal of a protection approach?

Thanks much for your suggestions,

Paul T

over 12 years ago

0 Paul Toffolo over 12 years ago

Prodigy 100 points

If anyone knows, part of what I'd be interested to know is the difference internally between a lin reg that is not negative transient rated, and one that is.

Thanks again,

Paul

0 Ron Michallick over 12 years ago in reply to Paul Toffolo

TI__Guru*** 139846 points

Hello Paul,

Bi-polar devices that withstand negative input voltage have only resistors and PNP emitters on the Vin node.
Any device with a NPN collector on VIn node can not tolerate negative input voltage.

The TL783 has a high drop out voltage of several volts. So it can't use used with 12V input.

Regards,
Ron Michallick

Power management

Power management forum

TL783 for ISO 7637?