pullupswitchesvoltage
I am new to electronics. Iam designing a simple circuit where I have to make a digital switch:
Here is what I have designed in Proteus:
There are 2 issues:
What changes should I make here?
I would say no. The specification does not mention anything higher than 100mA. Although these figures are accompanied by a voltage (for instance 50 mΩ at -2-4V) that does not mean that 4V is directly applied to the switch, because then the current would be 4V/50 mΩ = 80A!
The voltages matter in a switch too because the switch experiences the voltage when it is open, and it comes into play at the moment when the contact is being made or broken. Voltage causes arcing of switch contacts. It also plays a role in breaking through the thin film of oxidation. Note how conservative the 24V switch rating is. The current must be only up to 25 mA if you want to open and close the switch at 24V.
Even if you don't plan on changing the switches while current is flowing, the data sheet does not mention anything about carrying more than 100mA.
Idea: use the switches to control transistors to deliver the current.
Try
simulate this circuit – Schematic created using CircuitLab
The switches don't carry any signifigant current. Closing either of them turns off the output, at the cost of 50uA current from the source (trivial unless you're trying to run off a small battery for a long time).
I've not done the work of picking a suitable P-channel MOSFET. You should choose one with a low Rdson.
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