PWM Modulator

If you ever thought of experimenting with pulse-width modulation, this circuit should get you started nicely. We’ve kept simplicity in mind and used a dual 555 timer, making the circuit a piece of cake. We have even designed a small PCB for this, so building it shouldn’t be a problem at all. This certainly isn’t […]

Mini Lithium Torch

This mini pocket torch combines the advantages of Lithium button cells with a super-bright white LED. The lithium cells are small, have a long shelf life and have very little self-discharge. The LED has very high efficiency, an extremely long life expectancy and a modest current consumption (20mA). In combination this results in an exceptionally […]

Pulse width modulator by LM3524

* use a large surface ground track/fill for this circuit, otherwise the LM3524 will not work reliably! * mount the two potentiometers through the enclosure, as shown in the picture on the start of this page (these pots are used to control the frequency and duty cycle) * the driver is based on the LM3524 […]

Pulse Width Modulators using LM339

The first example uses the standard op-amp oscillator circuit to generate a triangular waveform which is level-shifted and fed to a comparator (e.g. LM339) to give the PWM waveform. Most people will want to use two comparators rather than one op-amp and one comparator so that is what we show here. Read More Source: […]

PWM Driven Safety Strobe by UC3842 – TL3842

You’ve seen them when you’re driving. Mailmen use them, snow plows have them. This is a schematic of the circuit inside.This was taken from a popular unit available at NAPA auto parts stores. It’s amazing how simple it is for a PWM circuit. It uses a UC3842 (here a TL3842 clone) pulse width modulator to […]

Simple Function Generator

Simple triangle-wave generators have a weakness in that the waveform of their output signal normally cannot be modified. The circuit presented here makes it possible to smoothly alter the waveform of a linearly rising and steeply trailing saw-tooth signal through a symmetrical triangle-wave to a slowly trailing, steeply rising linear sawtooth. The wanted waveform may […]

PWM Modulator Using Op-Amp

This is a simple PWM modulator circuit. Comparing the message signal to a ramp or triangular waveform is the simplest way to produce a PWM signal. When the input is greater than the triangular waveform (the carrier), the resulting output is high, when the input is less than triangular waveform, the output is low. So, […]

Texas Instrument TL494 Operational Test Circuit Diagram, Waveforms and Datasheet

If you need a power-supply control device which has all the functions of Pulse-Width-Modulation control circuit in a single chip, you may consider the TL494 PWM control circuit. Below we provide you with its Operational Test Circuit Diagram, Waveforms and the datasheet. According to the datasheet, the Texas Instruments TL494 offers the flexibility to tailor […]

National LM555 Datasheet, Replacement for SE555/NE555 Series and the Connection Diagram

The following LM555 Datasheet consist of informations about a highly stable device for generating accurate time delays or oscillation. As stated in the datasheet, this LM555 is direct replacement for SE555/NE555 since the LM555 has an additional terminals for desireable triggering or resetting. The illustration beside shows the top view of LM555 Connection Diagram which […]

Pulse Width (PWM) Controller Circuit

A LM3900 quad operational amplifier can be used to build a pulse width (PWM) controller. The LM3900 was chosen because it only need single supply voltage of 4 to 30 V. This circuit can give 100 percent pulse-width control.  A1 op-amp forms a 1 kHz oscillator, generating a square wave oscillator for the basic oscillation. […]