Input voltage 5.5V-12V, (no more than 12V would be the best option for protection of LED board according to accurate test)
Buck Voltage Current Regulated circuit
Gives 80%~94% efficient output
Measures 19mm in diameter, and 8mm in height
Multi-Mode: Low(5%)/High(100%)/Middle(35%)
Designed for XM-L, SSC P7 & Cree MC-E LED for maximum output 300lumen-900lumens(C bin), 900-1000LM of Cree XM-L
1xLED+, 1xLED-
Prewired, ready to use
Output Voltage:
2.8A(High)~ 1.38A(Middle)~0.25A(Low) --at any voltage level from 5.5V to 13.2V---Current regulated
Caution: No more than 3 D-size Li-ion Batteries (4.0V~12.0V) for protection this LED board,When overheat, automatically switch to Low mode, and flash one time per 5 seconds. When return to safe temperature, automatically switch to previous mode.
Measurements
Type: LDV9
Diameter: 19mm+21mm
Height: 10mm
Tested with XM-L2 (And it did survive).
The driver is not a 3A driver, but a 5A driver!
Driver has memory
A short off/on will change to next mode.
Modes: Low, medium, high
Medium uses pwm at 1kHz with 30% duty cycle.
Low uses pwm at 1kHz with 5% duty cycle.
High
The driver needs about 5.5 volt before the output is stabilized, but it does not stabilize at 2.8 or 3A as the specifications says, it delivers 5A to the led.
The efficiency is also lower than specified, probably because of the higher current.
The low voltage warning activates at 5.5 volt.
When slowly increasing the voltage, the driver turns on at about 4.8 volt and goes out of low voltage warning at about 5.7 volt.
There is no pwm in high mode, only some high frequency noise.
When the driver gets hot is uses pwm to reduce output.
Low voltage is signalled by two fast off then 5 seconds low light.
Medium
In medium the average led current is about 1.5A. The low voltage warning activates at 5.6 volt.
For medium the driver uses a 1kHz pwm with 30% duty cycle.
Low
In low the average current is about 0.2A (Remember due to pwm the actual current is 5A, but only in short pulses).
For low the driver uses a 1kHz pwm with 5% duty cycle.
Conclusion
The driver works fine and the heat warning is a nice feature.
But the high current has a great risk of damaging the leds, the current must either be reduced or the driver must be used for leds with higher current rating.
Notes
I am not very impressed with lck-led's custom service. I got one wrong driver and one driver that were far outside specifications (This one). I have sent a couple of emails to them, I got one question back after two weeks: did I want money back or a new driver. There was no explanation if it covers one or both of the problems and I do not know if they have sent me a new driver (That was my answer).
I have the same driver and I have a problem becouse in low and medium mode led blinks a little every (i think) 5s. It is not any protection feature, and PWM. In high mode all is ok, only in low and medium something like this is happening.
If you don’t mind me going on a bit about this, how about some 100µF (tantalum SMD) for each Ampère at 1 KHz? (loosely based on 1000µF for 1 A at 50 Hz)
Or would it trouble the FET?
I assume it would be better for the LED and for its efficiency.
Soldering looks pretty sloppy, efficiency is rather weak (talking about all modes). I also have one of those and blinks randomly. I have one with a big inductor that also does 5A and that one always get hot to 105C and output drops immediately to low mode. I am sure these drivers are random as random they can be. I do not know why they choose such small inductors for such currents and I am sure that one is not a high-end inductor for it's size.
A 7135 does not use pwm, but most drivers using a 7135 adds pwm. The pwm can be anywhere from 100Hz up to above 10kHz.Using a high pwm frequency with the 7135 do have some problems, because the 7135 is not that fast to turn on, especially not when driving a pack of them from a single microprocessor output pin.
Here is an example from one of my driver tests:
The microprocessor has its output on for nearly 2us, but the led is only on for about 0.1us. The rest of the time is used for the 7135 to turn on.
Really?
So, just to verify, a 7135 just burns off excess voltage?
Like when you run a LED on 3 Volts, from 6 Volts battery, with one 7135, the 7135 uses as much power as the LED??
:^\
I wouldn’t trust a DMM’s view on the average voltage.
For the rest this is all a bit over my head…
I find it hard to believe though that a, say, 100kHz PWM-ed power supply can’t be smoothed to its average with a coil and a capacitor, like a class-D amp loaded with a speaker.
How about this cute thingy to modify into a driver?
Probly not, but it’s tiny enough!