Making a 1 Watt LED Driver Circuit at 220V
White LEDs no doubt are the potential illuminating alternatives of the upcoming days, mainly because these units can be illuminated brilliantly at comparatively minimal wattage. For instance, 1 watt LEDs are becoming widely used these days because of their tiny dimensions and powerful point luminosity outputs, and as typical these demand merely a watt at 4 volts for producing spectacular illuminations.
Here I am going to demonstrate how to construct a really simple 220 V or 110 V powered 1 watt LED driver circuit, that would probably charge you not higher than 1/2 a dollar, apart from the LED, naturally.
In the circuit diagram we notice a relatively easy capacitive power supply circuit for operating a 1 watt LED, which can be comprehended with the following details.
The 1uF/400V capacitor at the input structures the center of the circuit, and features as the principal current limiting element of the circuit.
The current restraining functionality ensures that the voltage employed on the LED by no means surpasses the obligated safe degree.
Nevertheless high voltage capacitors possess one significant problem, these usually do not control or are unable to prevent the preliminary turn on mains power in surge, which happen to be disastrous for almost any electronic circuit, LEDs are simply no exceptions.
Introducing a 56 Ohm resistor at the input enables you to bring in certain damage regulation , but nonetheless it on its own cannot genuinely accomplish the total shielding of the needed electronics.
An MOV would definitely do the job, additionally how about a thermistor? For sure, a thermistor could certainly as well be an accepted strategy.
However these are fairly at the more expensive side and we are here referring to an affordable variation for the suggested layout, therefore we may wish to dismiss whatever that would go across a buck mark so far as the entire expense runs.
Therefore I considered a creative method of changing an MOV with a common, inexpensive substitute.
What could be the purpose of an MOV? It's to push the starting blast of high voltage/current to earth such that it can be grounded before hitting the LED, in this instance.
Wouldn't a high voltage capacitor apply the same process of operation if attached across the LED itself. Indeed it might certainly function the identical manner like an MOV.
The figure displays the insertion of an additional high voltage capacitor straight across the LED, which sucks the immediate invasion of voltage spike in the course of power switch ON, it does this at the same time charging up itself, and in the course diffuses virtually the whole preliminary voltage in-surge which becomes mostly the concern with capacitive type of power supply circuits.
The outcome as presented in the picture is a fresh, protected, easy and a cheap 1 watt LED driver circuit, that could be constructed directly in the home by any electronic hobbyist and employed for individual delights and application.