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?
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?
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?
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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I would recommend to start with reading some good books on amplifiers design. Bob Cordell, Douglas Self.
Here is an example of a simple amplifier with a single power supply by Rod Elliott:
El Cheapo - A Really Simple Power Amplifier
Here is an example of a simple amplifier with a single power supply by Rod Elliott:
El Cheapo - A Really Simple Power Amplifier
Hi
Just try to building this http://www.diyaudio.com/forums/chip...-watt-transconductance-current-amplifier.html to know how sound superior current amp is...
Just try to building this http://www.diyaudio.com/forums/chip...-watt-transconductance-current-amplifier.html to know how sound superior current amp is...
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.
That's what you have to work with. You'd need two bridged amplifiers and a floating load to double the voltage swing.
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