Linear amplification through transisters?

[dddriveman]

I am a mechanical guy and i have a little knowledge of electronics. So i am going to post a question that i am sure someone else can answer for me. Is there any way to amplfy a voltage by means other than another power source? I was thinking transisters, is that possible and how would i do that?

Thank you for your help

[Rickertsen2]

Originally Posted by dddriveman

I am a mechanical guy and i have a little knowledge of electronics. So i am going to post a question that i am sure someone else can answer for me. Is there any way to amplfy a voltage by means other than another power source? I was thinking transisters, is that possible and how would i do that?

Thank you for your help

What exactly is it that you are trying to do? It sounds like you are trying to amplify a voltage to a higher voltage than is available? I could be of alot more help if you could give more specifics on what it is you are trying to do. What is the intended purpose of this circuit?

[dddriveman]

Originally Posted by Rickertsen2

What exactly is it that you are trying to do? It sounds like you are trying to amplify a voltage to a higher voltage than is available? I could be of alot more help if you could give more specifics on what it is you are trying to do. What is the intended purpose of this circuit?

Actually i need to amplify the amperage not the voltage

[ttedrow]

Originally Posted by dddriveman

Actually i need to amplify the amperage not the voltage

Amplification can be done many ways. Transistor and op amps are two of the more popular ways But to help you on this problem we need some information on the source and destination impedance and signal levels.

[dddriveman]

Originally Posted by ttedrow

Amplification can be done many ways. Transistor and op amps are two of the more popular ways But to help you on this problem we need some information on the source and destination impedance and signal levels.

we are using it to power a small motor connected to a 5v output. I am not sure what the impedance is.

[Rickertsen2]

Originally Posted by dddriveman

we are using it to power a small motor connected to a 5v output. I am not sure what the impedance is.

your still holding out on us here. We need more info. What will the input to this circuit be? What power is available? How big is this motor? Elaborate a bit more on this 5v output. We would be glad to help but we need to know what it is we are helping with.

[Al Skierkiewicz]

Originally Posted by dddriveman

we are using it to power a small motor connected to a 5v output. I am not sure what the impedance is.

D,
I am going to go out on a limb here and guess that you have a 5 volt motor you are trying to turn on with a logic digital output switching between 5 volts and ground. You are running into a problem that the motor won't start by itself even though you are sure the digital output is going to 5 volts when you want it to. So here is one method to get this working, it will allow turning in only one direction though. You need a NPN transistor capable of the current needed by the motor to run. I like 2N3055 but they are big and clunky (TO-3 case). Connect one terminal of the motor to the power supply 5 volts. Connect the other side to the collector of the transistor. Connect the emitter of the transistor to power supply ground, and connect the base to the digital output.(It may be wise to start with a 1000 ohm resistor in series with the base lead.) When the digital output goes high, the transistor collector and emitter will act as a short, grounding the lead of the motor attached to the collector. The motor is now effectively connected to 5 volts and ground. If the motor is turning the wrong direction, simply reverse the leads of the motor. Does this help?

[dddriveman]

Originally Posted by Al Skierkiewicz

D,
I am going to go out on a limb here and guess that you have a 5 volt motor you are trying to turn on with a logic digital output switching between 5 volts and ground. You are running into a problem that the motor won't start by itself even though you are sure the digital output is going to 5 volts when you want it to. So here is one method to get this working, it will allow turning in only one direction though. You need a NPN transistor capable of the current needed by the motor to run. I like 2N3055 but they are big and clunky (TO-3 case). Connect one terminal of the motor to the power supply 5 volts. Connect the other side to the collector of the transistor. Connect the emitter of the transistor to power supply ground, and connect the base to the digital output.(It may be wise to start with a 1000 ohm resistor in series with the base lead.) When the digital output goes high, the transistor collector and emitter will act as a short, grounding the lead of the motor attached to the collector. The motor is now effectively connected to 5 volts and ground. If the motor is turning the wrong direction, simply reverse the leads of the motor. Does this help?

That answers it thanks

[ttedrow]

Hopefully you know that this motor you are asking about cannot be used on a FIRST competition robot.

[Mike Betts]

Originally Posted by dddriveman

...Is there any way to amplfy a voltage by means other than another power source?...

Without a energy storage device or external power supply: You can amplify the voltage at the expense of the current and you can amplify the current at the expense of the voltage.

There are no free rides in life (and no perpetual motion machines!)...