
In some PLL application, sometimes we need to provide lock indication when the PLL is in locked state. The simplest one is binary indication, 0 or 1 to correspond with lock/unlock condition. This condition should be easy to be presented with a LED lamp. The schematic diagram shows a lock-detection scheme [...]
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The circuit below is a schematic diagram of a fast pulse detector. At 100 ns or wider pulse width, the detection should be error free. At 60 ns pulse width, the detection error should be under 10%. This circuit should be used to detect at least 100 ns wide pulse to ensure an [...]
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Pulse position modulator can be easily built using 555 IC. Here is the schematic diagram of the circuit: Pulse position modulator modulate the on-period while keeping the fixed off-period. Pulse position modulation might substitute pulse-width modulation in some application. The main difference between pulse position modulation (PPM) and pulse width modulation (PWM) is [...]
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Pulse width modulator produce a PWM signal, a pulse with a constant frequency but with the duty cycle vary according to a modulating signal. Here is the schematic diagram of pulse width modulator circuit using 555 IC as the active component: This pulse width modulator circuit need external pulse train input to trigger [...]
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This is an application that can be used to adjust LED brightness while maintaining superior color quality. This application uses pulse width modulation (PWM) dimming technique. This application can be used for single-line scrolling displays, transportation road signs, simple scoreboards, ever-expanding advertising markets encompassing convenience gas stations, shops, stadiums, and stores. Following figures shows color [...]
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This is a Programmable Levels High Speed Pulse Generator circuit. This circuit consist of Lilliputian dimensions associated with the sub-micron geometries of many analog and most digital processes also advanced CMOS logic gates or analog comparators. Here is the circuit : The advanced CMOS logic gates or analog comparators is used to create faster [...]
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