220 Ac Powered White Led's

Description :

This is the simple version of a white LED lamp that can be directly powered from mains.
It can give ample light even for reading purpose. Capacitor CX along with diodes D1 through D4 forms the AC step down circuit. CX reduces high voltage AC from mains to a low voltage AC which is rectified by the diodes D1-D4.

Circuit :

Capacitor C1 removes ripples from AC so that low voltage DC is available to power the LEDs.CX is the X rated AC capacitor that reduces AC voltage through capacitive rectance property. Resistor R1 is very important to remove the stored voltage from CX when power is switched off. This prevents lethal shock.
Resistor R2 limits the inrush current.

Home Inverter

INVERTER FOR 100 W LOAD

  

Description :

                  Here is a 100 Watt inverter circuit using minimum number of components.I think it is quite difficult to make a decent one like this with further less components.

                  The IC1 wired as an astable multivibrator produces two 180 degree out of phase 100 Hz pulse trains.These pulse trains are  preamplifed by the two transistors.The out puts of the transistors are amplified by four transistors (two transistors for each half cycle) to drive the inverter transformer.The 220V AC will be available at the secondary of the transformer.Nothing complex just the elementary inverter principle and the circuit works great for small loads like a few bulbs or fans.If you need just a low cost inverter in the region of 100 W,then this is the best.

DC LED Driver

Introduction

DC powered LED lighting circuits can vary from trivial single LED/series resistor combos to simple analog current regulators to more complicated switching power supply circuits such as this project. There is a tradeoff between simplicity and circuit capabilities. This more complex circuit adds features such as regulated light level across a wide range of input voltages and automatic circuit shutoff on low input voltage. By using a high frequency switching regulator, the power loss associated with the current dropping resistors found in simpler circuits is reduced. This offsets the power consumed by the circuit's active parts. This circuit can power 10 white LEDs at 24mA of current with only 98mA of input supply current when running on 12V. LED intensity is fully regulated across the entire operating voltage range. This circuit was inspired by F. Garcia's IR LED video illumination circuit, published in the July 2001 edition of Nuts and Volts magazine. I modified the LED count and feedback circuit, and added the important low voltage shutdown feature.