
Light dimmer circuit is used to control the lamp for arbitrary brightness. This dimmer circuit work for incandescent lamp, not a fluorescent one. The dimmer circuit here work for both 110V and 220V AC. Here is the schematic diagram of the circuit: /caption] Dimmer Wiring Diagram The dimmer circuit is [...]
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This circuit is similar with our previous dimmer circuit, but the gate control is full-wave rectified using diode bridge. This circuit can be used to replace electric switch for your incandescent lamp, brushed motor, soldering iron or heater. Here is the schematic diagram of the dimmer switch: Please note that his dimmer switch [...]
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Notch filter is known as band-cut filter or band-reject filter. The fuction of this filter is to remove some frequency portion of a signal. The schematic diagram of this filter circuit, a second order notch filter is depicted in the figure below. The formula is actually complicated, but by taking the R3=R4 and [...]
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This is circuit of soft light dimmer. This circuit uses the IGBT STGP10N50A and the TS555 timer as main components. Here is the circuit: The timer is triggered on the zero crossing voltage pulse. The time constant determined by C5/R14+R15 that is used to determine the conduction angle. The T2 – T3 inhibits [...]
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Using a single supply quad comparator LM339, LM239, LM2901, LM2901V, NCV2901, or MC3302, we can build a square-wave oscillator with simple circuit and formula. Here is the schematic diagram: This circuit is suitable if you need many square-wave oscillators in one circuit, since the quad packaged comparator provide four comparators in one single [...]
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The excellent high input impedance, high slew rate, and high voltage qualities of CA3140 op-amp make it suitable for Wien-bridge sine wave oscillator. The basic circuit for Wien-bridge sine wave oscillator is shown in the figure below (the upper part). You can see the formula in the figure, when R1=R2=R, and C1=C2=C, then the formula [...]
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