Describe the behavior of the RPI RESET CIRCUIT (note that J2 resets the Raspberry Pi Zero if pin 2 is pulled to Ground). - What happens when the switch is pressed? - Why do you think this circuit was designed this way? Could it have been simpler? - Do you have any improvement suggestions?
What happens when the switch is pressed?
The circuit (as shown) will not work as intended. R3 is much too large in value (4.7 Meg) to cause the MOSFET to activate because, its gate to source has a 100 kΩ pull-down resistor (R7). This means that the maximum gate source voltage that can be produced is about 70 mV and, this is insufficient for the MOSFET to activate. The MOSFET indicated has a gate-source threshold voltage of 1.3 volts minimum.
The circuit is flawed but, if R3 were less than circa 22 kΩ it would be redeemable.
Why do you think this circuit was designed this way? Could it have been simpler? - Do you have any improvement suggestions?are all opinion based questions ... they are not allowed here ... please rephrase them, or remove them \$\endgroup\$