Circuits & Schematics Signal Processing, Filters

An interesting variation on the theme of digital to analog converters (DACs) is the digital potentiometer (DPOT). In addition to being able to output a voltage proportional to a digital value when used as a multiplying DAC (MDAC), the DPOT can also ...

Frequent design idea contributor, Peter Demchenko, recently published “Extending the resolution of a peripheral DAC” ( Reference 1 ). In it, Peter describes an inverting dual-supply amplifier circuit that he says is intended “ to ...

By decoding the commands sent by a direct-broadcast satellite receiver that uses the DISEqC (digital-satellite-equipment-control) protocol, you can troubleshoot the commands or simply listen in. Eutelsat Corp offers the DISEqC protocol. The ...

There are several applications in which pulses longer than the set width are to be detected, ignoring the other short pulses. We are familiar with the missing pulse detector circuit, which detects the occurrence of a missing pulse in a pulse train ...

On two days in the course of every year, one in March heralding the start of spring and another in September marking the first of fall, the Earth’s axis of rotation aligns perpendicular to the rays of the Sun. These days are the equinoxes ...

A traditional implementation of an absolute-difference function comprises a difference circuit followed by an absolute-value circuit; the entire circuit requires at least three op amps. The design problem is complicated in single-supply-only ...

Whenever I find myself harboring a constantly nagging thought, I know I will eventually have to get busy and find a way to put it to rest. When I read EDN’s Design Ideas, I look for the range of frequencies over which the circuit will ...

Low-frequency filters, particularly at audio frequencies, usually take the form of active filters. These filters eliminate expensive inductors with windings of many turns. Both analog and digital active filters are most compatible with large-scale ...

High-speed DACs offer differential outputs, but, for low-end ac applications or high-precision level-setting applications, a single-ended current-output DAC with a differential-conversion circuit provides a novel approach to generating ...

Introduction In some applications it is necessary to transmit square waves across a long cable. However, long cables typically have high capacitance, which can significantly affect the signal’s wave shape. As such, the signal’s ...