Simple Tranformerless Power supply


It is very easy to convert 220 Volt AC to DC for powering electronic circuits. Any DC voltage from 3 volt to 36 volt can be generated from 220 volt AC using appropriate value of X rated capacitor and Zener diodes. The X rated capacitor drops 220 V AC to low volt AC. This can be rectified to DC by a Rectifier diode and smoothed by a Filter capacitor. By selecting a required value Zener, regulated DC can be obtained. But the only drawback of the Tranformerless power supply is its low current, so only light loads can be used. Here explains the design of a 4.7 Volt 4.6 Milli Ampere Tranformerless power supply to power PIR sensor .

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AC Powered PIR Light


A Simple design of PIR Light using Tranformerless Power Supply and Triac for driving the load. Too compact and can be enclosed in a small case. The light turns on when the PIR sensor detects human movement and turns off after the preset time. Re triggers in another movement. Its range is 30 cm to 10 meters and time delay, 30 seconds to 3 minutes both can be adjusted using the presets in the PIR sensor Module.

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Fast Charger for Car battery



Here is an efficient Car battery charger for fast charging the Car battery. It is a 5 Ampere charger with Digital Volt and Ampere Meter to display the charging voltage and current. Since the charger provides maximum 5 Amps current, battery can take high current it needs to charge very fast. As the charging process completes, current flow reduces to zero and will be displayed in the meter. So it is easy to confirm whether the battery is fully charged or not.
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Automatic Car Battery Charger


This 5 Amps charger automatically stops charging when the terminal voltage of battery rises to 13.7 V thus preventing over charging. If the battery voltage drops below 11 V, Charger turns on and starts charging. Check it……….
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Wireless Electricity Generator


Wireless Electricity Generator
Here is a High Efficiency Wireless Electricity Generator project. Usually we make a simple wireless electricity generator to light 1.8 volt Red LED. But here the efficiency of the Wireless Electricity Generator is increased to light 1 Watt White LED Bulb that requires 3.6V. It generates voltage and current even to light a Strip LED. Try it and see the wonder of LED lighting without a battery connection.

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How to connect Digital Volt Ampere Meter


How  to connect Digital Volt Ampere Meter
Digital Volt Ampere meters are now available to measure DC voltage and Current. It can be connected to the output of the Power supply. So the output voltage and current to the load is displayed in the meter. If a battery is connected to the power supply for charging, we can see the current consuming by the battery during charging. When the battery is fully charged, current drops to zero which indicates the termination of charging. If project is connected, the voltage and current to the project is displayed.
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Power regulation using IC


Voltage regulation through Fixed Voltage Regulator IC is the most suitable method.78xx series positive and negative regulators are widely used to get fixed voltage to drive loads. Here explains a circuit design to get regulated voltage from a 12 volt 500 mA power supply .This circuit can deliver 5 volts at 300 mA for driving a load.

The circuit is Voltage and Current regulated and with Polarity and Surge protection components.
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