Mike Irwin

The circuit in Figure 1 is a variation on the familiar integrator/comparator triangle-wave oscillator, which you typically implement with two op amps. An integrator and a comparator connect in a positive-feedback loop; the comparator drives the integrator and vice versa. A...

Professional-audio equipment commonly uses Analog Devices‘ high-performance, quad-voltage-controlled SSM2164 attenuator. The control response is –30 dB/V, with 0 V producing unity gain. Attenuation increases as the applied control voltage increases in the...

FETs find common use in VCAs (voltage-controlled amplifiers) and attenuators, in which the FET serves as a variable resistance. A control voltage applied to the gate sets the channel resistance and overall circuit gain. You frequently need to select individual FETs because of...