Using Luxeon LED Driver with Picaxe 08m

[djmikeys]

I am trying to use Luxeon LEDs and their driver with the Pic 08m chip. pleae see

http://www.luxeonstar.com/item.php?id=5187&link_str=240::241::1395&partno=3023-D-E-350

I have connected the driver pins to the following:

Led+ ........ led+
led- ........ led-
ctl(0-5v)........ picaxe pin
ref+5v ..... 5v
Vin+ ......... 6V
Vin- .......... Ground

When I program the pic to control the Led (flash on and off) there is no response, it just stays on.
Any ideas?????

 

[sghioto]

Are you using the 5 volt reference voltage to power the picaxe ? Would need to see your code and schematic as YOU wired it, otherwise would just be speculating.

Steve Ghioto

 

[lbenson]

Figure 15 in the Buckpuck pdf, "Interface to PIC or other microcontroller", is confusing to me, but has the cathode of the LED connected to "GND" (on the PIC) as well as to LED-, and Figure 13 also has LED- connected to COM (common, I suppose). Do you have it this way? As sghioto says, post code and schematic (and maybe photo).

Good find on the part to have micro control of on/off, strobe (and dimming?). I wired up several of the besthongkong 1W/350mw constant current drivers with Cree LEDs, but there's no one-connection method of controlling the LEDs.

 

[Peter M]

3021 working ?

Hi, can you verify that the 3021 works properly by conecting a swtich (or a piece of wire) across the REF and CTRL pins as per fig 11 (dont worry about the pot), dont forget to disconnect the PicAxe output pin first though. <|;-)
It should be OFF when they are connected, ON when open

 

[newboy]

Hi I believe that the Buck Puck requires 5v on the control wire to turn off the output, thus turning off the LED for some reason.
You may want to try this driver as you can shut it down with 0v from picaxe chip and 5v is full on
http://www.dotlight.de/shop/product_info.php/cPath/100_108/products_id/443

 

[djmikeys]

I bought the driver that newboy suggested and works fine, what I am now tryinh to do is have the LED have a range of brightness, I am using the pwmout function, I can control the brightness to a certain level but then the led will just turn off when the 'cycles' drops below 30. I am using the led and driven with the pic 08m and an IRF630 transistor.
Here is an example of the code I am using just to test brightness':


main:

pwmout 2,255,20

goto main


Any ideas on how to control the leds brightness from on to off in slow gradual stages?

 

[yamato96]

This code refers to a mod i made in a IKEA wall moon lamp .
It uses 1 picaxe 08m + 1 Luxeon Rebel Star white - 130 Lumens + 3 LED UV 5mm 40mW + 1 IFR540N + 3 x 1.2v AA Recharg. batts (3.6v 1000 mA)(no resistors !).

 

[djmikeys]

Thanks for the reply,
I have tried your code with the IRF630 and it only dims to about half brightness, If I use the IRF540N like you suggest will this bring the Luxeon down until it turns off?

 

[Dippy]

mshorter: I haven't checked the code suggested, but sometimes it depends on your circuit as much as the code.

I am using the IRF630 in a project right now and have had to play around with components to drive this MOSFET with a fast pwm. Its nothing to do with LEDs though, so my circuit will not be useful to you.

As I said, I haven't looked at code so maybe the answer is within....

Post your circuit though; just in case.

(Query: That BuckPuk is an expensive way to drive an LED or two innit?)

 

[djmikeys]

I hopefully have attached a circuit diagram........

I am using this expensive driver because I assumed it gave the best results for the luxeon star LEDs

 

[eclectic]

Mark.
Following on from Dippy's last comment.

Do you simply wish to control the current through a few
350 mA LED's?

Manual 3, page 6 second diagram could be used as a basis for LED control.
(With resistors of the correct value and power-rating.)

Cost of a ULN2003 = 41 pence.
Cheaper than a FET and much cheaper than a controller.

And very simple to control with PWMOUT.

Or have I misunderstood?

e.

 

[Dippy]

mshorter: how are you powering PICAXE?
Please label legs/connections and redo your schematic I can't follow it.
I don't even know, from that, whether you've connected anything up properly.
Put in ALL the legs, pins, whatever and mark them precisely.

Please, please make it easy for others to help as they are giving their time FREE of charge.

 

[djmikeys]

Sorry, I was in a bit of a rush this morning, attached is a diagram of more details.

Eclectic: I have had a look at the data sheet for the ULN2003, and am alittle cofused, what exactly does it do? and how would i use it in the context of my work?

 

[eclectic]

Quick reply, before I sign off.

Please print out and read pages 5 and 6 of Manual 3.

e.

 

[xnederlandx]

That circuitry diagram seems wrong. Dont connect 'Led -' to the transistor, only' IN -'.

For code,

start:

symbol pin = 1
w0 = 0;

fadeup:

PWMOUT pin, 249, w0

pause 3

let w0 = w0 + 1

IF w0 = 1000 THEN
goto fadedown
ENDIF

goto fadeup

fadedown:

PWMOUT pin, 249, w0

pause 3

let w0 = w0 - 1

IF w0 = 0 THEN
goto fadeup
ENDIF


goto fadedown

 

[eclectic]

MShorter.

First, apologies for my mistake in post #11; you're Mike not Mark.

Last year, I played with making bike-lights,
using 2803's to control both

a. Eight 5mm LED's and

b. Two 1 watt LED's (for serious rear-lights).

If you're interested, I can dig out the circuits.

e.

 

[yamato96]

Here's my circuit.Powered by three pack NiMH 1,2v 1300 mA. Havent tested autonomy.Maybe tomorrow post photo here and video on youtube.