Free electronic circuit design and schematic diagram
Using an RS232 port, we can generate square wave oscillation when transmitting data, and this can be “misused” as signal generator (square wave generator). This is a PC Signal generator produce a square wave in audible frequency range. This circuit utilize a transmission of a “U” character from ASCII character set. This character has binary value of 01010101, making it […]
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Mono-stable multivibrator circuit generates a fixed pulse width when receiving a trigger signal on its input. The pulse width of the output is fixed regardless of the input pulse duration/width. In practical application, the width of the output pulse is determined by choosing the right components values for certain application. In today’s digital electronics, mono-stable function can be easily implemented […]
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The requirement of a continuity tester is that its current should be small enough to not destroy the tested circuit. This simple circuit inject not more than 0.6 mA current into the tested path in the tested circuit. The schematic diagram describes all the circuitry of the circuit. This circuit is used to test if two point is electrically connected […]
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The voltmeter shown in the schematic diagram below has very high impedance. The range selector uses conventional voltage divider resistors, but since the following pre amplifier uses JFET, the divider can be designed using very high resistance series resistors. This DC voltmeter circuit also featured with low drift. This circuit uses a pair JFETs, which is configured in a balanced-bridge […]
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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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Because the differential input capability of the AD532, algebraic solution of several interesting functions such as difference of squares, (X2-Y2)/10V is allowed. The following figure shows us about the configuration of AD532 in the square mode, with a simple unity gain inverter connected between one of the signal inputs (Y) and one of the inverting input terminals (-Yin) of the […]
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For convenient reading, the display of this tachometer circuit show inthe reading in hertz directly. The conversion time will be equal to the gating time, which is 0.1 second with pin 11 of the ICM7027A connected to Vdd, make the display show tens of hertz at the least significant digit. An ICM7207 can be used with a 6.5536 MHz crystal […]
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