Camera Board Power Circuitry Testing #5
Description
Introduction
Only you can test the Camera Daughter Board Power Circuitry! The Intention behind the power circuitry on the camera daughter board was to allow the toggling of power to the board to allow the camera to cool down. This will be an essential function to operating the camera in space.
The Theory
The circuitry implements two MOSFETs to control power to the board. The control input is connected to the gate of the NMOS Transistor seen below. When the control input goes to a logic "high," the NMOS transistor is intended to pass ground to the gate of the PMOS transistor which should turn the transistor on, connecting the input power to the daughter board 3.3V line. When the control input goes to a logic "low," the NMOS transistor is intended to be off and the input power line is then fed to the gate of the PMOS transistor which should keep the input power line separated from the daughter board 3.3V line.
Is there an issue with this conception of the operations of this circuitry? Are different transistors suggested?
The Possible Testing
Voltage levels should be taken to verify operations of the circuitry. For instance, when 3.3V is applied to the control input on the gate of the NMOS transistor, does ground pass through to the drain of the NMOS transistor/ the gate of the PMOS transistor? Additionally, what is the voltage on the source of the PMOS transistor in this case? Replicate these same measurements but for also when the control input is set to ground.
Please let me know if there are any issues or concerns that arise from this basic functional tests!