AC to DC 90 Watt Switching Power Adaptor

Under Category : Switching

AC to DC 90 Watt Switching Power Adaptor Circuit AC to DC switching power adaptor circuit with maximum output power of 90W. Switching power supply is built using a high voltage power switching regulator IC MC33374 and some other additional components. The MC33374 IC is a monolithic high voltage power switching regulators that are specially [...]

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0-1000 Volt Regulated High Voltage Power Supply IC 7805

Under Category : Power Supply

1000 Volt DC to DC Regulator Circuit Input voltage from high voltage DC DC converter is 12V AC at 800mA current and then converted to DC through a bridge rectifier Diode 1A. The voltage output of converter circuit can be adjusted in the range of 0-1000V DC. This high voltage DC DC converter uses the [...]

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Isolated RS422 Interface Circuit and Layout

Under Category : Other Circuits

Isolated RS422 Interface Circuit Figure 1 shows the circuit diagram of RS422 interface. Connector K1 is linked to the serial port of the PC, power to the PC side of the circuit is derived from the signal lines DTR and RTS. Positive supply is derived from RTS and negative supply from the DTR line. Optical [...]

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RS-232 Reset for Microprocessor

Under Category : Microcontroller

RS-232 Reset for Microprocessor Introduction This circuit allows a remote microprocessor to be reset by a controlling host by sending a break signal over an RS-232 or RS-422 serial line. If the remote machine resets into a simple program loader program, it is possible for the host to halt and restart, or halt and reload/restart [...]

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10.58 to 10.74 MHz VFO Oscillator Circuit

Under Category : Oscillator

Figure 1, below, shows the 10.58 to 10.74 MHz VFO oscillator circuit. Yes, this is the same circuit that was presented last time, but I’ve re-drawn it to show the Colpitts oscillator more clearly. “L” is approximately 1.5 uH; 19 turns in a T50-6 core (yellow). The value of C6 is found experimentally. I used [...]

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Output Relay Delay Audio Amplifier Circuit

Under Category : Power Amplifier

Output Relay Delay Audio Amplifier Circuit This is a simple circuit which I built to one of my audio amplifier projects to control the speaker output relay. The purpose of this circuit is to control the relay which turns on the speaker output relay in the audio amplifier. The idea of the circuit is wait [...]

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12V Stroboscope 250-400V DC Circuit

Under Category : Other Circuits

The stoboscope tube needs about 250-400V DC to operate. This high voltage is generated using simple voltage step up circuit built from transistors Q1,Q2 and transformer T1. This circuit gives out about 230V AC voltage which is then rectified with rectifying bridge U1 (must have at least 400V voltage rating) and stored to the main [...]

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