During normal operation, Q5 is on, U1 is on, D12V0 is 12V,
When the input is reversed, the D35 conduction clamp is at a few V, Q5 is turned off, and U1 is not turned on to complete the protection.
Q5 Will it withstand reverse voltage when it is connected in reverse?
Delon 发表于 July 13, 2020
Except for U1, all the devices on the left are removed, and it is sufficient to ground the U1 pin 4 with a resistor.
Misa 发表于 July 13, 2020
Like, great
Alphonse 发表于 July 13, 2020
When Q5 is connected in reverse, U1 will burn down, and the internal freewheeling diode of u1 will be directly added by the voltage of Q5, which will burn down the freewheeling diode.
Serra 发表于 July 13, 2020
If conditions permit, add a diode to the power supply input to protect the point; the reverse cut-off, no loop.