I am using LTC4267 IC as a over voltage protection device. I have set the over voltage to 36v and the device is working fine. I have given a load of 1A. I have given 28v supply and 100V supply using diodes ORing circuit such that
1. If 28V is ON and 100V is OFF, then device input is 28V. The device works fine.
2. If 28V is ON and 100V is ON, then device input is 100V.
In second case when the 28V is ON for some duration, the device works fine and suddenly if 100V is switched ON, then the device gets damaged.
This happens only when 1A load is applied. Without load it works fine for this case also.
I have almost 10 devices like this.
Please help me to solve this problem.
The 100v is coming from the External supply. The MOSFETs are still
functioning without any problem.
The diode D3 is an SMBJ diode with a cutoff voltage of 36V.
My requirement is that :
The supply is given as step i.e for time 't1' there will be 28v supply and
suddenly after 't1' the voltage increases to >40V and continues for
time 't2'. At that time the output of the device should be 0.
After 't2' the input voltage again falls to 28v, and at this time the
output should be 28V.
The Device works fine exactly as above without any load connected to it.
But if a load is connected (tried with 0.5A load), then the device fails
even with a step of 50V.
Please help me in solving this.
There are no remaining ICs to test. Could you provide any samples?
Thanks and Regards
On Tue, May 1, 2018 at 2:58 AM, Sal.Afzal <