Is the Voltage at Point A Still 5V with V_in at 0 in a Transistor-Diode Circuit?

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SUMMARY

The discussion confirms that in a transistor-diode circuit with an input voltage (V_in) of 0V, the voltage at Point A remains at 5V. This conclusion is based on the absence of current through the 1000 ohm resistor, resulting in no voltage drop across the base-emitter junction of the transistor. Consequently, the transistor is effectively off, leading to an open circuit condition where no current flows through the 100 ohm resistor, thereby maintaining the voltage at Point A at 5V.

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Clandry
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I just wanted to see if I am understanding this circuit correctly.
Let's say the input voltage (V_in) is 0.
This means:
1) no current through the 1000 ohm resistor
2) no 0.7V drop from the base to emitter
3) transistor is pretty much off
4) The circuit is open, thus no current goes through the 100 ohm resistor either
5) voltage at A must be 5V
 

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Correct.

ehild
 

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