Hi
This is my first attempt at using transistors in a circuit, so confidence is not high. The circuit is powered by 24vDC, regulated down to 5v for the debounce and logic but has to switch the 24v via a PNP (not an NPN).
The mechanical switch SW1 is normally closed (so the debounce is 'tuned' for opening) and the PNP transistor Q2 should behave as normally closed, opening the 24v circuit when SW1 is opened (when also the green LED (D2) goes out, the red LED (D2) lights and the buzzer sounds).
I've test built this on a breadboard (excluding the voltage regulator circuit) using 3.3v to represent the 5v and 5v to represent the 24v so my question is: when I connect the voltage regulator circuit and push 24v through Q2, will this circuit release the magic smoke and/or do I need to change the value of the resistor R6?
The circuit appears to do what I need but any advice on what I could do better/differently/right would also be much appreciated.
PS, once I'm confident I have this right the main part of the circuit will be duplicated to provide a second switch.
This is my first attempt at using transistors in a circuit, so confidence is not high. The circuit is powered by 24vDC, regulated down to 5v for the debounce and logic but has to switch the 24v via a PNP (not an NPN).
The mechanical switch SW1 is normally closed (so the debounce is 'tuned' for opening) and the PNP transistor Q2 should behave as normally closed, opening the 24v circuit when SW1 is opened (when also the green LED (D2) goes out, the red LED (D2) lights and the buzzer sounds).
I've test built this on a breadboard (excluding the voltage regulator circuit) using 3.3v to represent the 5v and 5v to represent the 24v so my question is: when I connect the voltage regulator circuit and push 24v through Q2, will this circuit release the magic smoke and/or do I need to change the value of the resistor R6?
The circuit appears to do what I need but any advice on what I could do better/differently/right would also be much appreciated.
PS, once I'm confident I have this right the main part of the circuit will be duplicated to provide a second switch.
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