10 watt Led Driver

[Pulak]

And One more thing I need to know about transformerless capacitive supply for this module. How far should I do to build the circuit without using power transformer as used in mobile charger.

 

[audioguru]

EVERY electronic part I buy has a manufacturer's name and model number so I can look up its datasheet to see its detailed specifications. Why do you buy unknown garbage?

Oh I forgot. I bought a bag of blue LEDs made in India. The store (Sayal) has everybody working there from India and there was no manufacturer's name, no model number and no datasheet. Only half of the LEDs worked and the few that worked had visible flaws. But they were very CHEAP (cheep?)! Never again, but their American surplus products are excellent with low prices.

 

[Pulak]

LM 317 has the output current of 1.5A and LM 338 has the output of 5A. So the current requirement is only 350ma for this module and LM 317 can give. Or, is it like when voltage is increased the current also increase proportionately!

 

[Pulak]

EVERY electronic part I buy has a manufacturer's name and model number so I can look up its datasheet to see its detailed specifications. Why do you buy unknown garbage?

Oh I forgot. I bought a bag of blue LEDs made in India. The store (Sayal) has everybody working there from India and there was no manufacturer's name, no model number and no datasheet. Only half of the LEDs worked and the few that worked had visible flaws. But they were very CHEAP (cheep?)! Never again, but their American surplus products are excellent with low prices.

I agreed with you also, audioguru. But I am from India, what can I do. I need it very badly to build it to save much power on bills.

 

[audioguru]

My mains electricity is reliable and is cheap. It comes from water turbines at Niagara Falls and from nuclear generator plants. LED light bulbs are expensive and will last longer than me so I do not use them inside my home but I have many (28?) solar garden lights in my backyard. My electrical utility company gave away LED Christmas tree lights, compact fluorescent light bulbs and solar garden lights. I asked how many solar garden lights am I allowed to take and they said as many as I want. I should have taken hundreds but I took only ten.

 

[mvs sarma]

I HAD ORDERED 5 LOT ON EBAY.IN AT A TOTAL OF 170\
let me get we will both make

 

[Tony Stewart]

Use a CPU heatsink with fan and connect all in series. Use a small 1R in series direct or power N_ch MOSFET on low side.

Your LED may consist of 3 or 4 chips in series ( each with a Vth of 2.85V ( very dim)

If they get hot, the voltage will drift down. ( Shockley effect), and thus draw more current.. so dont let them get too hot to touch.

You can monitor current with a 50mV shunt R or current meter and direct connect them or use a power MOSFET with < 100mΩ RdsON on the low side.
Since 3 units range from 30~36V, you can expect the MOSFET to need a Heatsink mount.

I do this all the time as well as connect the 10W LEDs direct to PC PSU 12V with a 50mV current sense shunt to verify quality of LED. Often long cable R gives the desired calculated current limit from a fixed V.

These run off 12.0V SMPS at desired current with no other parts connected with 30AWG magnet wire to 18AWG feeder. ( the other parts on board not used) on MC-PCB which has microvias for improved resistance.

I chose ~5W so they sufficiently bright and cool with exactly 3.0V per LED.

Your results may vary.