current vs voltage transistor amplifier?

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If I were to add a voltage amplifier to a circuit. how would it differ from a current amplifier?
using NPN type.
and what would the differences in the two look like?

and could you bias a transistor with a diode and resistor? (diode to provide for
limiting to 0.7v and resistor to provide the voltage) if thats even a good way to do it?
 
If I were to add a voltage amplifier to a circuit. how would it differ from a current amplifier?
using NPN type. and what would the differences in the two look like?

Voltage amplifiers have high input impedance and low output impedance. Current amplifiers, the opposite.
http://www.ittc.ku.edu/~jstiles/412/handouts/Chapter 1/Current and Voltage Amplifiers.doc.

A bipolar transistor IS a current amplifier, but it is usually configured to operate as a voltage amplifier.
Diodes can be used for biasing if there is too much thermal instability, as in power amplifier output stages.
http://people.uwplatt.edu/~drury/bjt_bias.pdf
BJT Bias Design
 
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How do I make an amplifier with equal current and voltage gain on the output? can it even be done? or is there no such thing? Or no use for such a device?

and how would you get full rail to rail voltage swing on an amplifier with a single ended power supply? (0v to +v but no -V)
what kind of circuit would that require using power transistors? would that even be possible? how would you make something close to that for an audio amp?
 
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How do I make an amplifier with equal current and voltage gain on the output?
can it even be done? or is there no such thing? Or no use for such a device?

Hi,

It is a ludicrous concept. Current and voltage gain are independent.
Amplifiers use voltage, current depends on the load impedances.
FWIW the current gain of most amplifiers is vastly higher than the
voltage gain, but is determined by voltage gain and impedances.

rgds, sreten.
 
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