Free electronic circuit design and schematic diagram
This amplifier circuit is very popular audio power amplifier circuit type. We call it a complementary since the final transistors is an NPN-PNP pair, each with the same characteristics. This circuit produce an AB class amplifier, since each transistor works in slightly more than half cycle of the signal. There is overlap area when both transistor conduct a current, […]
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Interfacing high power load can be done in many ways, such as using voltage divider resistors, transformer, or optocoupler. In the circuit shown below , an optocoupler method is presented. This optocoupler serve the logic level translation with flexible input, accepting wide range of voltage level, which is suitable for many high power load/devices. To couple a high-voltage load to […]
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Logic indicator circuit / logic probe is used to identify logic level at any point of logic circuitry. The indicator can be visual (using LED, LCD, of 7 Segments) or auditory (using beeper or speaker). This circuit has a audible indicator, with the help of a loudspeaker to produce indication tone. Using the opamp,U1, as schmitt trigger, the Audio oscillator […]
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