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## Modulator vs Multiplier-Difference between modulator,Multiplier

This page compares Modulator vs Multiplier and mentions difference between Modulator and Multiplier. It mentions equations for both modulator and multiplier.

### Modulator The figure-1 depicts operation of a typical Modulator. It has multiple inputs usually two. In modulator, one input signal can modify or control the another input signal. In the figure, fA and fB are arbitrary functions of input signals v1(t) and v2(t) respectively.

For example,
If modulated signal Vm is Am*Cos(2*π*fm*t) and
if carrier signal Vc is Ac*Cos(2*π*fc*t+Φ) then
in the modulated signal output,
Ac varies according to amplitude of modulating input signal for amplitude modulator ,
fc varies according to frequency of modulating input signal for frequency modulator ,
and φ varies according to phase of modulating input.
Refer What is Modulation>> and types of analog modulations>> and digital modulations>> and Modulator and Demodulator>>.

### Multiplier The figure-2 depicts operation of a typical Multiplier. It is almost similar to modulator where in fA and fB both are linear functions of v1(t) and v2(t) respectively.

Multipliers are used in nonlinear analog signal processing, mixing, frequency translation, modulation and demodulation etc. There are different types of multipliers as mentioned below.
• One Quadrant multiplier
• Two Quadrant multiplier
• Four Quadrant multiplier

Following are the applications of multipliers.
• as Frequency doubling
• as positive divisor and negative divisor to perform division operation.
• used to perform square root operation
• used to perform cube root operation