Free electronic circuit design and schematic diagram
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 for the CD4046B. The PLL system uses phase comparator […]
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Autoranging is useful to extend the measurement range of an available ADC (analog-to-digital converter). Autoranging will best implemented for multiplexed input. LTC1257 is appropriate for system autoranging, adjusting an ADC’s full-scale range. During the conversion process, U2 and U3 receive the full and zero scale codes, respectively, that correspond to a selected multiplexer channel. For example, let channel 2’s span […]
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Transducers is used in video system to convert optical signal to electrical signal in the acquisition. In the display, transducer is used to convert electrical signal back to light. Transducers often have a transfer function (the ratio of signal in to light out) that is unacceptably nonlinear. The newer technology of video camera transducers (the improved versions of vidicon-like tubes […]
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A PLL system can be used to implement an FM demodulator. When a PLL is locked on an FM signal, the VCO tracks the instantaneous frequency of that signal. Since the VCO output tracks the FM signal, and the VCO input voltage is proportional to the VCO output frequency, then the VCO input will be equal to the demodulated signal. […]
Read moreThe 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 error free performance. [Circuit’s schematic diagram source: […]
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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 an identical bias resistor, RB, is used […]
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Fading a video signal is not as simple as attenuating the whole signal, since there will be a point where the sync amplitude becomes too small.
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