Re: Designing a multi-range milli-ammeter
There is another circuit that uses one transistor and shunt resistor to protect a meter movement.
As the current rises above a certain level, the transistor turns on and shunts the meter movement.
My google foo is failing me this morning and I can't locate an actual drawing as an example.
Of course, there is also the old standby of anti-parallel diodes across the meter terminals. While they may not stop the needle pinning, they will in most cases protect the coil from suffering damage.
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