So I have an odd problem with the LM324N.
I'm using it as a comparator. Its function is completely as expected if I use an LED and resistor as the output however if I try to connect the comparator output to a microcontroller so that I can use it to trigger external interrupts it triggers at half the voltage it should be.
This is not simply an issue with the microcontroller interrupt occurring without a sufficient signal, the actual output voltage of the comparator changes to half of the reference and the comparator becomes triggered at an input voltage that is half of the reference.
Can particular types of loads change the behaviour of the chip and why would that be the case?
Resistors and LEDS on output > works good
Microcontroller pin on output > triggers when voltage in is half of reference instead of equal to reference
Mind boggling situation, changed lm324n chips and same behaviour.
I'm using it as a comparator. Its function is completely as expected if I use an LED and resistor as the output however if I try to connect the comparator output to a microcontroller so that I can use it to trigger external interrupts it triggers at half the voltage it should be.
This is not simply an issue with the microcontroller interrupt occurring without a sufficient signal, the actual output voltage of the comparator changes to half of the reference and the comparator becomes triggered at an input voltage that is half of the reference.
Can particular types of loads change the behaviour of the chip and why would that be the case?
Resistors and LEDS on output > works good
Microcontroller pin on output > triggers when voltage in is half of reference instead of equal to reference
Mind boggling situation, changed lm324n chips and same behaviour.
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