Hello everyone,
I have a strange problem with the LTC4359CDCB, I hope someone can help me.
I am using the LTC4359 in three identical circuits connected in parallel on one board. I have used the schematic from the demo board DC1676A demo board, with only one difference, I used a different mosfet (SQJQ160E-T1_GE3).
Two circuits switch two batteries in parallel (23V) and an external switchable power supply (25V).
Now to my problem:
Above 20°C the circuit works as planned, but below 18°C only one circuit switches. Two circuits can be switched on a second circuit board.
If I only heat up the mosfet, the circuit works perfectly. The junction temperature of the mosfet is between -55 and +175°C and Vgs is 3V instead of 2V as in the example circuit.
I don't know exactly why the circuit reacts so sensitively to the temperature. Could a cold solder joint be causing the problem or does anyone have any other helpful ideas?
Regards
Patrick
