Any LED lamp is a set of LED emitters and a power supply (voltage converter) for them. LEDs have a very long service life and, while ensuring optimal parameters for their power, can work for many years.
Cause of failure of a lamp to 90% of cases the fault lies in precisely the electronic parts of the circuit. Therefore, if desired, the defective lamp can often try to repair yourself, at home. This article is intended for beginners and amateur radio provides a simple representation of the device and LED lamps, as one of the possible options.
The power supply (inverter driver) of the lamp is a small fee with radioelements which is disposed under the board with LEDs in its body-base. Such a driver may have a transformerless circuit, and may contain a small pulse transformer, transistors and ICs.
This article will be given a simple driver circuit not comprising a transformer, transistors, and ASICs. This scheme is applied, for example, in lamps «Jazzway» 8 with a power consumption W.
The resistor R1 in the circuit is needed to avoid significant inrush current at the time of switching on the lamp and serves as a "fuse". Capacitors C1, C2, C3 "quenched" part 220V mains voltage to an acceptable level.
Instead, these three capacitors can, of course, including one with capacity of 1.5... 2 microfarads. However, such a capacitor has been considerable size and may simply not fit into the lamp housing. It therefore applies the parallel connection of three capacitors with small dimensions. All capacitors in the circuit (except C5) should be taken with non-operating voltage below 400V.
As a rectifying diode bridge can be used microassembly or four diode type 1N4007. Resistor R3 serves to eliminate the current jump in the moment of switching and charging capacitor C5. Capacitor C5 - oxide (electrolytic).
It is used to smooth the driver output voltage ripple and it is possible to put more capacity than indicated on the chart, if allowed by the dimensions of the board and the housing. Resistor R2 is needed for rapid discharge of capacitors C1, C2 and C3 to prevent electric shock when replacing the lamp. A capacitor C5 R4 protects against breakdown in case of a break in the circuit of LEDs ( "burnout" of one or several of them).
Load drivers are 15 LEDs in series. By increasing the number of LEDs should increase the total capacitance of capacitors C1, C2, C3, C5 and capacitance on the output drivers.