
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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Fast peak detector requires special amplifier features. The output stage must have high slew rate to keep up with the intermediate stages of the amplifier. This condition causes either a long overload or DC accuracy errors. The amplifier must deliver large currents into the capacitive load of the detector to maintain a high slew rate [...]
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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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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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A fast peak detector similar but faster than previous peak detector, can be implemented using open loop configuration. Here is the schematic diagram of the circuit: In this design, D1 is the detector diode and D2 is a level shifting or compensating diode. A load resistor RL is connected to – 5V and [...]
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