Use the following instructions to
verify the overvoltage protection feature of
LM74912-Q1.
- Remove the input
33-V
TVS (D1) incase you want to set and test the input
overvoltage
threshold,
which is greater than the breakdown voltage (40V)of the TVS.
- Set the input supply voltage VIN
to 12 V and current limit of 10 A.
- Turn ON the power supply and
observe
start-up
of
output
voltage,
HGATE,
and DGATE.
- Slowly
increase the input voltage to 40
V.
Observe
the HGATE going low and turn OFF the load switch FETs (Q2 and Q4) when the input
voltage reaches
overvoltage
protection threshold of 37
V.