Archive for the ‘Basic Function Circuits’ Category
Pulse Width to Analog Voltage Demodulator
This is a schematic diagram of a pulse width to analog demodulator circuit. This circuit is used to demodulate the pulse width to analog voltage level. With input pulse width range of 0 to 1 microsecond, this circuit can produces Output range of 0 to 10 v. The input pulse is integrated and the final …[Read More]
Retriggerable One Shot with 556 IC
Retriggerable one shot/monostable multivibrator circuit is a flip-flop circuit which give active output when an input is present, and hold the state for a predetermined period before turns to inactive state. The difference between retriggerable and non-retriggerable is that retriggerable circuit gives period extension when the input is retriggered before the output changes to inactive …[Read More]
This is an interface circuit for digital data input. This circuit consist of touch button, op-amp, diode, capacitor and resistors. Any conductor surface can be used as the touch probe, such as a machine-screw head having comparable area around 0.5-inch-square or similar area of any pattern on printed-circuit board. This circuit need a DC power …[Read More]
Variable Frequency And Duty Cycle Oscillator
A discrete oscillator circuit shown in the schematic diagram below is a variable duty cycle and variable frequency oscillator, can be used to produce rectangular wave. This circuit has frequency range of 60 to 1,000 Hz. This circuit consist of one UJT (uni junction transistor) and two transistors that provide positive going output when emitter …[Read More]
Discrete 0.5-300 ms Monostable Multivibrator
Monostable multivibrator circuit produce a fixed pulse-width when the input is triggered. The input is fed to CR1, which should be an open collector source since the TR1 would short the input to ground during the active state appear on this circuit’s output. The output of this circuit is tapped from the collector of TR2. …[Read More]
Long Period SCR Timer
This is a SCR timer circuit. Here, SCR is used to drive the final actuator, the buzzer. The time constanst of this circuit is determined by R1 and C1. The buzzer will sound when C1 charges up to a desired level, it will cause the Q1 to conduct and triggers SCR1. The use of FET …[Read More]
Norton Amplifier with DC Gain Control
This is a Norton amplifier circuit with dc gain control. This circuit is formed by one section of an LM3900. This circuit has dc gain-control input ranges from 10 V for maximum gain down to 0 V for minimum gain. Here is the schematic diagram of the circuit:
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