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Analog multiplier AI simulator
(@Analog multiplier_simulator)
Hub AI
Analog multiplier AI simulator
(@Analog multiplier_simulator)
Analog multiplier
An analog multiplier is an electronic circuit that produces an output level that is the mathematical product of the levels of its two analog signal inputs. Such circuits may be used to implement related functions such as squares by applying the same signal to both inputs, and square roots.
Electronic analog multipliers are classified by their function. A single-quadrant multiplier permits only one, typically positive, level on the inputs. A two-quadrant multiplier permits one input signal to swing to positive and negative levels, while the second input remains positive. In a four-quadrant multiplier all inputs may swing to positive or negative levels, producing a positive or negative output level.
If one input of an analog multiplier is held at a steady voltage, a signal at the second input is scaled in proportion to the level on the fixed input. This may be considered a voltage-controlled amplifier or variable-gain amplifier. Applications are for electronic volume control and automatic gain control (AGC). Although analog multipliers are often used for such applications, voltage-controlled amplifiers are not necessarily true analog multipliers.[citation needed] For example, an integrated circuit designed to be used as a volume control may have a signal input designed for 1 Vp-p, and a control input designed for 0-5 V dc; that is, the two inputs are not symmetrical and the control input has a limited bandwidth.
By contrast, in what is generally considered to be a true analog multiplier, the two signal inputs have identical characteristics. Applications specific to a true analog multiplier are those where both inputs are signals, for example in a frequency mixer or an analog circuit to implement a discrete Fourier transform. Because the precision required for the device to be accurate and linear over the input range, a true analog multiplier is generally a much more expensive part than a voltage-controlled amplifier.
Analog multiplication can be accomplished by using the Hall effect.
The Gilbert cell is a circuit whose output current is a four-quadrant multiplication of its two differential inputs.
Integrated circuits analog multipliers are incorporated into many applications, such as a true RMS converter, but a number of general purpose analog multiplier building blocks are available such as the four-quadrant multiplier. General-purpose devices usually comprise attenuators or amplifiers on the inputs or outputs in order to allow the signal to be scaled within the voltage limits of the circuit.
Although analog multiplier circuits are very similar to operational amplifiers, they are far more susceptible to noise and offset voltage-related problems as these errors may become multiplied. When dealing with high-frequency signals, phase-related problems may be quite complex. For this reason, manufacturing wide-range general-purpose analog multipliers is far more difficult than ordinary operational amplifiers, and such devices are typically produced using specialist technologies and laser trimming, as are those used for high-performance amplifiers such as instrumentation amplifiers. This means they have a relatively high cost and so they are generally used only for circuits where they are indispensable.
Analog multiplier
An analog multiplier is an electronic circuit that produces an output level that is the mathematical product of the levels of its two analog signal inputs. Such circuits may be used to implement related functions such as squares by applying the same signal to both inputs, and square roots.
Electronic analog multipliers are classified by their function. A single-quadrant multiplier permits only one, typically positive, level on the inputs. A two-quadrant multiplier permits one input signal to swing to positive and negative levels, while the second input remains positive. In a four-quadrant multiplier all inputs may swing to positive or negative levels, producing a positive or negative output level.
If one input of an analog multiplier is held at a steady voltage, a signal at the second input is scaled in proportion to the level on the fixed input. This may be considered a voltage-controlled amplifier or variable-gain amplifier. Applications are for electronic volume control and automatic gain control (AGC). Although analog multipliers are often used for such applications, voltage-controlled amplifiers are not necessarily true analog multipliers.[citation needed] For example, an integrated circuit designed to be used as a volume control may have a signal input designed for 1 Vp-p, and a control input designed for 0-5 V dc; that is, the two inputs are not symmetrical and the control input has a limited bandwidth.
By contrast, in what is generally considered to be a true analog multiplier, the two signal inputs have identical characteristics. Applications specific to a true analog multiplier are those where both inputs are signals, for example in a frequency mixer or an analog circuit to implement a discrete Fourier transform. Because the precision required for the device to be accurate and linear over the input range, a true analog multiplier is generally a much more expensive part than a voltage-controlled amplifier.
Analog multiplication can be accomplished by using the Hall effect.
The Gilbert cell is a circuit whose output current is a four-quadrant multiplication of its two differential inputs.
Integrated circuits analog multipliers are incorporated into many applications, such as a true RMS converter, but a number of general purpose analog multiplier building blocks are available such as the four-quadrant multiplier. General-purpose devices usually comprise attenuators or amplifiers on the inputs or outputs in order to allow the signal to be scaled within the voltage limits of the circuit.
Although analog multiplier circuits are very similar to operational amplifiers, they are far more susceptible to noise and offset voltage-related problems as these errors may become multiplied. When dealing with high-frequency signals, phase-related problems may be quite complex. For this reason, manufacturing wide-range general-purpose analog multipliers is far more difficult than ordinary operational amplifiers, and such devices are typically produced using specialist technologies and laser trimming, as are those used for high-performance amplifiers such as instrumentation amplifiers. This means they have a relatively high cost and so they are generally used only for circuits where they are indispensable.