ISO5451-Q1: DESAT protection vs propagation time of automotive comparators

Bart

Part Number: ISO5451-Q1

Team,

we have a question about DESAT protection. If there is some reason to change DESAT reference voltage from +9V it is easy done with Zener diode. But if we want to change that ref voltage to higher (e.g. 10V) comparator is needed. All automotive comparators with supply >24V have propagation time >500ns. Is there another way to deal with?

Thanks for your help.
TI Customer

over 5 years ago

0 Audrey Dearien7 over 5 years ago

TI__Expert 4875 points

Hello,

You can utilize a voltage divider with reference to VCC2 as shown in the circuit schematic attached to increase the reference voltage.

Please let us know if you have other questions or concerns.

Regards,

Audrey

0 Kresimir over 5 years ago in reply to Audrey Dearien7

Prodigy 160 points

Hello,

I do not understand purpose of resistor connected to VCC (unmarked resistor). Is it mistake?

Regards.

0 Audrey Dearien7 over 5 years ago in reply to Kresimir

TI__Expert 4875 points

Hello,

I apologize for the confusion; the unmarked resistor is not a mistake. This resistor is now used with CDESAT to control the blanking time for DESAT protection in this configuration.

Regards,
Audrey

Power management

Power management forum

ISO5451-Q1: DESAT protection vs propagation time of automotive comparators