The circuit consists of a 12V DC supply, there is a GPIO to turn on the solenoid rated at 12V 500mA. Also, a manual switch is there to turn on the solenoid when needed.
The placement of LED and 1K resistor is such that LED would turn ON whenever Solenoid is turned on, be it either due to GPIO high OR by manual switch. My requirement is to Turn on a LED if Manual Switch is ON irrespective of GPIO level.
- Manual ON , GPIO ON : LED ON
- Manual ON, GPIO OFF : LED ON
- Manual OFF, GPIO ON : LED OFF
- Manual OFF, GPIO OFF : LED OFF
How can it be accomplished?
NOTE: TIP122 is transistor used. The diode is flyback diode