gain amplifiers
gain amplifiers
(OP)
Is it possible to design an amplifier with a gain < 1? If yes, how would I go about it? All the gain amps I find have a gain of 1 or higher.
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RE: gain amplifiers
Let assume a gain of 1/3
The wiring of basic DIFFERENTIAL amplifier:
input + --- R1.1 ( .1 AND .2 ARE THE ENDS OF R1)
R1.2 --- IN+ ---R2.1
R2.2--- GND
input- ---R3.1
R3.2 --- IN- --- R4.1
R4.2 --- OP.OUT
-------VALUES : --------------
R1= 3 * R2
R3=R1
R3 = 3 * R4
------------------------
INVERTING AMP:
omit R1 AND short R2.
IN+ --- GND
-----------------------
NON-INVERTING AMP:
omit R3 AND R4
R1= 2 * R2
IN- --- GND
RE: gain amplifiers
In the case, we need a high power or using in an Auto Gain Control circuit, sometime we need a variable attenuator. This type of attenuator we always use the active component to build it. It use the same technique as the amplifier to build it.
Expecially in RF circuit, we can find a lot of attenuators with FET inside.
RE: gain amplifiers
Vout=-(Rf/R)Vin
If Rf<R the amplifier will be producing output voltage smaller than the input voltage.
RE: gain amplifiers
RE: gain amplifiers