Hi all,
I am using MOSFET to switch on/off supply to one section of my circuit. Supply voltage is 3.3V
The circuit is attached here.
When PS_Control is HIGH, I get 3.3V.
But, when PS_Control is low, still I am getting approximately 1V at the output. But i want the voltage to be zero. Whats the reason for this? Do I need to modify the circuit?
When the MOSFET is OFF Test-Point VL_3.3V is floating .. and you have a tiny leakage current ..
Try to add a "dummy" load of, say, 100kΩ that will pull the voltage down to 0V ..
Unlike bipolar transistors, power MOSFETs have a considerable
gate capacitance that must be charged beyond the threshold
voltage, VGS(TH)
, to achieve turn-on. The gate driver must provide
a high enough output current to charge the equivalent gate capacitance, CEI
, within the time required by the system design.