Re: Driving a transistor base from a voltage divider

"Baron" wrote:

If the current through R1 + R2 is much larger than the required base
current then the junction will set the base voltage. That will allow
you to set the collector current anywhere between zero and maximum.

However for a switch the transistor would be hard on or hard off. In
which case a single resistor will limit base current to a safe level,
at the point where its switched hard on.

Thanks Baron, that is appreciated.

Speaking of switching the transistor "hard on", how (in the absence of load
charts for a particular transistor) do I determine a sufficient base current
to do this?

Thanks again,

Jon


.

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