Hi
I have designed a fan controller which is op amp driven
It uses an non inverting amp set up which is sensing voltage across a .01R So every 1A of load equates to 10mV across the current sence resistor.
The O/P of this is then fed in to a comparator with positive feed back.
Which switches a transistor to start the fan.
Question is i need a 1.7V reference voltage for my comparator.
Would a voltage divider be ok to use for this? the loading affect on the divider must be very small?
Is there an easy way to select the resistors. Or do i just select say R2 and experiment with R1 in the formula till i fine a good value?
Must be a better way lol
Is it best to use high values like 100K plus or keep it 10's of K's ?
Cheers
I have designed a fan controller which is op amp driven
It uses an non inverting amp set up which is sensing voltage across a .01R So every 1A of load equates to 10mV across the current sence resistor.
The O/P of this is then fed in to a comparator with positive feed back.
Which switches a transistor to start the fan.
Question is i need a 1.7V reference voltage for my comparator.
Would a voltage divider be ok to use for this? the loading affect on the divider must be very small?
Is there an easy way to select the resistors. Or do i just select say R2 and experiment with R1 in the formula till i fine a good value?
Must be a better way lol
Is it best to use high values like 100K plus or keep it 10's of K's ?
Cheers