Hi,
So this is my first arduino project, I am switching a transistor from pin13 when the voltage on A0 (ADC) falls below a certain value.
It's going to water my plant while I'm away for three weeks and it has to run on batteries so I dont want to waste any power. There will be 5V at the A0 pin >90% of the time, but when it takes soil resistance readings every 12hrs or so it will drop a few volts at that pin.
Will there be any current leakage into the arduino while it has 5V on A0?
Will there be current leakage through the pull up resistor if I use it?
Is it negligible?
If not, which is the most efficient option/less leakage?
Also one more thing: I'm using a ULN2803 darlington array to switch the motor, do these ICs need to have their inputs tied down or do they do it internally?
Cheers,
Cam.
So this is my first arduino project, I am switching a transistor from pin13 when the voltage on A0 (ADC) falls below a certain value.
It's going to water my plant while I'm away for three weeks and it has to run on batteries so I dont want to waste any power. There will be 5V at the A0 pin >90% of the time, but when it takes soil resistance readings every 12hrs or so it will drop a few volts at that pin.
Will there be any current leakage into the arduino while it has 5V on A0?
Will there be current leakage through the pull up resistor if I use it?
Is it negligible?
If not, which is the most efficient option/less leakage?
Also one more thing: I'm using a ULN2803 darlington array to switch the motor, do these ICs need to have their inputs tied down or do they do it internally?
Cheers,
Cam.
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