2 Quadrant and 4 Quadrant Multiplier

[Learner]

2 quadrant multiplier

Hi,
Can anyone help me understand what is the main difference between a 2 Quadrant and a 4 Quadrant Multiplier?

Thanks!

 

[gevy]

four quadrant multiplication

For 2 Quadrant Multiplier first input has single polarity and second input has any polarity.
For 4 Quadrant Multiplier both inputs have any polarity.

 

[Learner]

four quadrant multiplier

Hi Gevy,
Thank you so mcuh for your help! The reason I asked is because I am trying to figure out why this part GT4123A is a two-quadrant multiplier, because it seems that IN A, IN B and Vc can all take AC as input?



Data sheet click here

 

[echo47]

4-quadrant multiplication

The data sheet says Vc range is 0 to 1V, so VCA and VCB never go negative.

 

[Learner]

two quadrant multiplier

Hi echo47,
Yes, but if Vc is biased with 0.5V and coupled with an AC signal it would work as a 4 quadrant multiplier?

BTW, the frequency response chart in data sheet covers from 1Mhz to 100Mhz. Would this part work for audio frequency if an audio signal is placed at AMP A and AMP B?

Thanks!

 

[echo47]

4 quadrant multiplication

No, that won't give you 4-quadrant multiplication. The VCA and VCB inputs are still positive, so the multiplication is only 2-quadrant.

Even if you somehow managed to cause VCA and VCB to go negative, the multipliers would probably misbehave. 4-quadrant multipliers are usually more complex than 2-quadrant multipliers.

It should work fine for audio. Data sheet page 2 says the signal channel frequency response is within 0.05 dB from DC to 10 MHz.