Hi, I am thinking of building a PIC controlled inductance meter.
The goal is to use the PIC comparator to form an oscillator where the frequency (more specifically the period) is determined by an inductor under test. Then the PIC measures the oscillator period with good accuracy and can give an accurate inductance display.
The minimum inductance can be as high as 470uH and can be built in, and the inductor under test can be placed in series to add inductance (as the PIC can simply deduct the built in value to get the test value).
I've checked some other LC meter designs but they tend to use an LC oscillator and I would prefer a pure L based solution where L is directly proportional to period.
Does anyone know an oscillator format that would work in this situation using one comparator (or two comparators with the same +Vref)?
Thanks!
The goal is to use the PIC comparator to form an oscillator where the frequency (more specifically the period) is determined by an inductor under test. Then the PIC measures the oscillator period with good accuracy and can give an accurate inductance display.
The minimum inductance can be as high as 470uH and can be built in, and the inductor under test can be placed in series to add inductance (as the PIC can simply deduct the built in value to get the test value).
I've checked some other LC meter designs but they tend to use an LC oscillator and I would prefer a pure L based solution where L is directly proportional to period.
Does anyone know an oscillator format that would work in this situation using one comparator (or two comparators with the same +Vref)?
Thanks!