Circuits & Schematics - Oscillators - 5

The linearity of triangular waveforms makes the triangular- wave generator useful in sweep circuits and test equipment. For example, switched-mode power supplies and induction motor-control circuits often include a triangular-wave oscillator as ...

You can build a self-oscillating H bridge by replacing the pullup collector resistors of a classical BJT (bipolar-junction-transistor) astable multivibrator with PNP BJTs (Figure 1). Because this circuit oscillates at supply voltages as low as 0.6 ...

A design idea with a 555 analog timer that can generate an arbitrary triangle/sawtooth with its waveshape and frequency controlled by pots. If you could assemble the list of all the oscillators that have been designed around the 555 analog timer, ...

A resistive DAC in a resistive-feedback loop of an op amp lets you create an analog-digital-analog divider. The resistance, R WA , between the W and A terminals of the Analog Devices AD5293 (Figure 1) decreases linearly with increasing the ...

On June 12, 2011, the analog EE world lost a star when guru James M. Williams died. Jim’s hundreds of articles, books, and application notes were (and continue to be) a bottomless wellspring of information, inspiration, and the joy of seeing ...

Three-phase VCOs (voltage-controlled oscillators) see service in many applications, including power inverters and in electronic-music synthesis as control and modulation sources. A previous Design Idea describes a basis for a simple, three-phase ...

Examine a traditional Hartley oscillator circuit, and you'll note its trademark: a tapped inductor that determines the frequency of oscillation and provides oscillation-sustaining feedback. Although you can easily calculate the total inductance ...

Engineers have long used function- generator circuits employing analog integrators and high-hysteresis comparators. The outputs of these circuits often depend on variations in temperature, power-supply voltage, load, and parts. However, you can ...

The circuit works due to the fact that voltage increases or decreases linearly when a constant current flows into or out of a capacitor. If we manage to charge and discharge the capacitor with the same constant current, then the voltage of the ...

The 555 multivibrator circuit has become a default choice of many hobbyists and even professionals in the past 50 years. Its pair of equations for frequency and duty cycle easily gives capacitor-resistor combinations which satisfy the required ...