Free electronic circuit design and schematic diagram
Pulse position modulator can be easily built using 555 IC. Here is the schematic diagram of the circuit: Pulse position modulator modulate the on-period while keeping the fixed off-period. Pulse position modulation might substitute pulse-width modulation in some application. The main difference between pulse position modulation (PPM) and pulse width modulation (PWM) is that unlike PWM, PPM doesn’t keep constant […]
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Sawtooth wave oscillator is used in cathode ray tube deflection circuitry, in a PWM modulator, or in a analog to digital conversion. You can also use it in your own design, only your imagination can limit its application. Here is one example of the circuit: The frequency is determined by C1, R1, R2, R3, and R4. This frequency formula can […]
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PLL oscillator is used to get very stable frequency woth very low distortion of sine wave output. The stability is equal to crystal-based oscillator, and the low distortion level of the sine wave output is equal to LC based oscillator. The method of PLL control in PLL oscillator is done by adjusting the frequency of sine wave VCO (voltage controlled […]
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In the simplest form, current to voltage converter can be implemented as simple as one resistor, since a voltage is developed when an electrical current flow against a resistance. The problem is that the resistance always affect the current by decreasing the current flow, and the current to voltage conversion is not accurate. In some cases, the resistor that convert […]
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Integration is one of basic signal processing that can be done in analog domain. Using operational amplifier (op-amp), integration operation can be done with very simple circuit with very high accuracy. Here is the schematic diagram of an integrator circuit: The resistor R2 should have the same value with R1 since R2 is employed to minimize the offset error due […]
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This circuit is conventional “Pierce” type oscillator that uses a JFET. The circuit uses fundamental mode crystals. It has decent performance and reliability if we use a low noise JFET. The feedback is controlled by the C1 Capacitance from drain to ground. Adjusting the frequency can be done by adjusting a shunt capacitance C2 across the crystal. The crystal works […]
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This circuit is a simple crystal oscillator that can be operated in overtone mode. Overtone mode permit the operation at higher frequency than specified by the crystal. The circuit uses a grounded base amplifier configuration, and place the crystal as a series resonator. The transistor Q1 is biased in the active region as an amplifier. L1C1 is a resonant circuit […]
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