This is quick post about 3W constant current LED driver
which I was design to combine with some homemade furniture piece. The main
components of this system is
LM311 voltage comparator and
IRF9540 P-Channel MOSFET.
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| Schematic of 3W LED driver module |
This module is design to drive maximum of two 3W high power LEDs
and it requires 8V - 10V DC (500mA) power source. In this given configuration
this module may not need any heat-sink (for IRF9540) and consume maximum of
500mA of power.
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| Breadboard version of 3W LED driver |
At prototyping stages we test this module using 9V DC (1A)
power supply with two 3W LEDs (EDEX-3LA1-E1). I developed final version of this
module using piece of strip-board and PCB design is not done.
Comments
1 question though. 3w power leds are rated at 700 ma. why go for 500 ma?
1. Fix IRF9540 source and drain connections.
2. Add buck switcher output
circuit to IRF9540.
In the past, I've used TI's LM3410 sepic led driver with a aaa (1.5v), but the maximum constant current is about 700ma. I'm hoping to find something that gets closer to 1A.
Liner Technology developed several high current LED drivers (ex: LT3743, LT3476, etc.) but I never used them because these ICs are bit difficult to find in local market place (and even in eBay also).
the LEDs I have are,
LED, HIGH POWER, 5000K, 70CRI, 275LM
Series: LUXEON TX
LED Colour: White
Luminous Flux @ Test: 369lm
Forward Current @ Test: 1A
Forward Current If Max: 1.2A
Forward Voltage @ Test: 2.86V.
could you please help me what should be the specifications of the driver??