Circuits & Schematics Oscillators

A few years ago, I worked at a disk-drive company. We had a plating facility that required square waves to drive the high-voltage plating operation. The challenge was that the square wave's pulse width had to be variable, along with the duty ...

Plumbing a laboratory with a standard frequency makes a lot of sense if the lab uses multiple frequency counters, spectrum analyzers, and other frequency-dependent test equipment. Rather than spending time keeping all of the instruments' ...

EDN Most oscillator circuits include a nonlinear amplitude control that sustains oscillations at a desired amplitude with minimum output distortion. One approach uses the output sinusoid's amplitude to control a circuit element's ...

Gavin Watkins EDN A recent project evaluated the feasibility of a dynamic load modulation (DLM) RF power amplifier for 5G. DLM amplifiers typically use high-voltage varactor diodes in their output network, which need to be driven by high-speed ...

Jordan Dimitrov EDN Pulse-width modulation (PWM) is the best conversion method to use for digitally-controlled variable DC voltage sources requiring high accuracy and resolution. Invented 50 years ago [1, 2], the PWM approach is widely used today ...

Glen Brisebois EDN I recently had the opportunity to investigate a new micropower 6-MHz LTC6255 op amp driving a 12-bit, 250k sample/sec LTC2361 ADC. I wanted to acquire the FFT of a pure sinusoid of about 5 kHz. The problem is that getting the FFT ...

Davinder Oberoi EDN A common circuit in electronics is the square-wave, astable multivibrator (one-shot), which is useful for various purposes, such as timing circuits and audible alarms. The most common way to generate the desired square wave is ...

Shyam Tiwari EDN Digital oscillators often generate TTL- or CMOS-level outputs, referred to ground. Generating a symmetric bipolar output with respect to ground presents a challenge. In this design, four 1.5 V flashlight cells create 3 V voltage ...

Moshe Gerstanhaber EDN The multivibrator is a common circuit that consists of an amplifier with both positive and negative feedback (Figure 1a). When the output is positive, the positive input terminal equals ½V+, and the voltage at the ...

José M Miguel EDN Testing audio-noise-reduction circuits, PLLs (phase-locked loops), and audio-frequency filters may require a noisy sine wave, one that is summed with white noise. Using a typical computer sound card, free software, and an ...