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Pnp version of common collector

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maicael

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i was wondering what should be the value of the resistor at the base of the transistor before an input voltage is applied in ratio to the emitter resistor.for example the emitter resistor value is 1k resistor with Vcc applied to it while the collector is connected to ground.would the base resistor be significantly larger or smaller.
i am using a bridge rectifirer and a 10k pot as the voltage source which is applied at the base of the transistor
 
A common-collector transistor circuit does not need a series base resistor.
The emitter voltage of the PNP common-collector "emitter-follower" will be about 0.7V more positive than the base voltage and the base current will be the collector current divided by hFE which is a very low current.

If the Vcc is 12V then the maximum collector current in the 1k emitter resistor is 12V/1k= 12mA.
If the hFE of the transistor is 200 then the maximum base current is 12mA/200= 60uA.
 
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