Just have a problem about this nice bridge power keys gate booster. It have inputs INA and INB what are steered by bridge controller given meanders, but ENA and ANB all the time was unused (high).
Now we introduced a bridge current (7 nsec fast) measurer thus there are wish sometimes shut down the SMPS what means put both ENA and ENB (1. and 8. foot) to GND.
Result is short-circuit with plenty of smoke and IC is carbonized.
Thus, WHY that so simple inner circuit into booster is demolished by ENA or ENB puting to GND?
And why it isnt said in datasheet in the clear sentence, to never allow ENA set into zero?

 

Sorry but can you please explain it better, your sentence doesn't make sense?

 

Just have a problem about this nice bridge power keys gate booster. It have inputs INA and INB what are steered by bridge controller given meanders, but ENA and ANB all the time was unused (high). Now we introduced a bridge current 7 nsec measurer thus there are wish sometimes shut down the SMPS what means put both ENA and ENB (1. and 8. foot) to GND. Result is short circuit with plenty of smoke and IC is carbonized. Thus, WHY that so simple inner circuit is demolished by ENA or ENB put to GND. And why it isnt said in datasheet in the clear sentence?

WAG

Likely back EMF from a inductive load abruptly being shutdown passed from the output stage. Some sort of snubber network on the bridge output to shunt or dissipate the energy might help.

 

nsa spook: THNKs, this helped a lot. One virtual beer from me. Transformer distance was about 5 cm afar. Snubber already was there.

 

nsa spook: THNKs, this helped a lot. One virtual beer from me. Transformer distance was about 5 cm afar.

Did you resolve the issue?

 

Yep! Thanks.