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How to install LED floodlight
From;    Author:Stand originally
With freeboard diode of bright white glow does floodlight, it is the wonderful method of section report. Because want to had used LED to just shine quite, installation rises can appear troublesome, and outfit is not quite actual still in the sitting room (travel of about 100 ability) . If install,be in the toilet the effect is very good. Because toilet area is small, brightness demand is not high also, the author's toilet installed 12 LED to shine quite, but must stick LED cent on the ceiling again dispersedly, span had better not be less than 10 centimeters, otherwise the effect is poor.

Paralell connection rises these 12 LED, former I plan to use transformer step-down. But the transformer of 3V of 220V / is bought not easily. Be forced to use wave of filter of commutate of capacitance step-down classics later power supply, if pursue,1 is shown. Roads of such one incoming telegram are very simple, but above carrying electricity of 220V communication city. Insecure. Additional because capacitance C1 is bigger, the meeting when operating switch K1 produces scintilla. After using period of time, I change it into power supply of switch power source again. This ability get sth done once and for ever.

Graph 2 it is the circuit that improves finally, it divides composition by two. Picture of before half part is in dotted line casing, it is the switch power source that a 220V communication turns 6V into dc. This power source can be replaced with mobile phone charger, reason herein of its job principle need not give uncecessary details. Second half part is a dc that use 6V falls the switch power source of 3.2V.

In step-down switch power source, integrated circuit 555 make generator of a rectangular wave, adjust its occupy sky comparing, can achieve adjust the purpose that outputs voltage. Because the rectangular wave of 555 output passes Q1 to charge to C4, the voltage of two end of C4 outputs voltage namely. The bulk that rectangular wave constitutes sky comparing decided C4 charges the discretion of voltage, occupy sky comparing to be 50% when, output voltage is 1/2 namely 3V. Change the size of the R1 in circuit, changeable rectangular wave occupies sky comparing, thereby the purpose of voltage of implementation adjustment output. Because LED is received directly,carry in output, if output voltage is too tall, be about to burn out LED, when so change R1 adjusts output voltage, the holiday that must change LED into Ω of a 18 is laden (namely 3.2V180mA) , monitor its at the same time two upright voltage, cannot exceed 3.2V absolutely! Had adjusted R1 that is to say, decide on a verdict, just can receive on LED.

The LED parameter that city makes work is uneven, want to choose beforehand, electric current passes to want for the ability of 15mA in 3.2V indelicacy, and brightness should agree. Additional. Work because of two dynatron in switch condition, loss is very small, not calorific. Need not add radiator so.




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