
This circuit detect the amplitude of audio signal, suitable for audio level detection that demand for high precision. Amplitude detection or signal envelope detection is usually implemented using a peak detector. An ideal amplitude detector give continuous level at any time because the amplitude of a sine signal (every signal can be seen as sine [...]
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Using only a single transistor and few passive components, you can build a fairly sensitive peak detector. circuit This peak detector circuit is suitable for audio application, since the average sum of positive and negative cycle of audio signal has equal value. You can find a peak signal although you only detect the peak of [...]
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Implementing peak-detector circuits is very easy with the CA3130, as shown in schematic diagram of this circuit. The figure below shows the schematic diagram of the peak detector circuit. The upper section is peak-positive and the lower section is peak-negative circuit. Please note that with large-signal inputs, the bandwidth of the peak-negative circuit [...]
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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. ThisĀ condition should be easy to be presented with a LED lamp. The schematic diagramĀ shows a lock-detection scheme [...]
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A simple half-wave peak detector using a single transistor is very compact and low cost, but if the application require precise detection for signal under 100mV then that circuit become useless. Here you can use more precise half-wave peak detector circuit using only a single op-amp with few passive components. Look at the circuit’s schematic [...]
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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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