Basic transistor switch

basicswitchestransistors

I'm just an amatuer working with some electronics at home. I am trying to use an NPN transistor as a switch. 9v on the Emitter, 6v as the control on the Base to activate the switch, and I'm going to get 9+v on the Collector.

However, the voltages end up subtracting. When measured I only get 3v.

Am I setting this up wrong? I'm hoping to boost the voltage in this switch.

schematic

simulate this circuit – Schematic created using CircuitLab

Best Answer

I would think that your circuit would produce around 5V or more at the emitter of the NPN transistor, so I am thinking there is something not quite right somewhere. However your circuit will never work the way you want it to, so I am hesitant to spend too much time thinking about it.

Here is one circuit that will work the way you want. Just apply your 6V control signal to 9V_ENABLE. VCC_9V_SWITCHED will be 9V when 9V_ENABLE is high. You don't say how much current you are expecting. So I am not sure if the BSS84 is really a good choice. If you add a current requirement on the 9V supply, someone might be able to select a better choice for M1.

Good luck and keep at it!

schematic

simulate this circuit – Schematic created using CircuitLab

Related Topic