Free Simple Circuit Diagram
Pulse generator circuit shown in the schematic diagram below produces square wave pulse with adjustable duty cycle/active factor. The benefits of using this circuit are low components count and high stability of its output frequency. The frequency of this pulse generator is fixed, the frequency f depends on the value of R and C1, following the formula of f=1/(1.1*R1*C1), where […]
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Despite the popularity of single-supply ICs, a negative control voltage is still required by some applications. Modern, inverted R-2R ladder DAC and op amp is the solution for this purpose. This approach offers lower supply voltages, higher speed, and smaller packages when compared with older DACs containing standard R-2R ladders. An output swing from 0V to 2.5V is produced by […]
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A window comparator formed by two op-amps packaged into IC1 is the heart of the circuit below. With this technique, we can detect precisely and symmetrically either the positive or negative peak value reached by the monitored signal. The op-amps outputs are smoothed by C4, R7, and R8, mixed by D1 and D2, and feed the LED driver Q1 with […]
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To add PWM intensity control to connected LEDs, a switched-LED power supply approach can also be used. A circuit using a PWM-based supply to provide additional intensity control to some LEDs is shown on figure below. The PWM waveform and I²C commands to the LED driver is sent from the same microcontroller. A software routine can control the PWM waveform. […]
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