Wiring help on DX SKU 4735

rizky_p

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i tried wiring as per DX thread instruction but the board get really hot even when 2xAA is connected and even hoter whileusing single 14500.

Draws 1.7A from single 14500, current to led is 850ma which indicate something is wrong. Connected to Cree P4.

I post a picture on how i wired this up. Can anyone suggest other solutions?
DSCN7570.jpg



Thanks.
 

VegasF6

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Hmm, I am anxious too to find out how to wire this, as I have 3 of them sitting on my desk in front of me. I had planned on wiring it just like you as per the pics on DX. Did you only try one of them?

What is the brown component at the top of the board? Some sort of filter cap? I see on the older model some people soldered there connections to each side of it?

I also wonder about the empty solder pad on the upper left where the diode is.

I am afraid I really don't understand much about how this works, but I thought the sense resistor was just that, only to sense current (or voltage?) and control the inductor. When I traced the pad marked - to the left side of the resistor it shows that they are connected. Does that mean by wiring it this way it passes the full current through the sense resistor and overheats it? Or perhaps R2 is the sense resistor? Sorry I am rambling, but I am TRYING to help :)

So I guess my best guess is my first one, one to each side of the filter cap I will give it a shot if I can ever get my test bench set up, and if I can find the darn 115V muffin fans I had set aside for this purpose.
Good luck.
 

rizky_p

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So I guess my best guess is my first one, one to each side of the filter cap I will give it a shot if I can ever get my test bench set up, and if I can find the darn 115V muffin fans I had set aside for this purpose.
Good luck.

Thanks for the help, i tried 2 board and still get the same reading one identical to another, i have one more board untested but i can safely assume that it will have the same result.

Anyone please?
 

marschw

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This is a bit of a shot in the dark, but have you tried replacing the brown capacitor with a higher value? (And soldering the leads to either side of the capacitor as well, as VegasF6 suggested).
 

VegasF6

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This is probably small consolation but I am having my father look at these for me Sunday. He is (to me at least) a bit of an electronics guru, so hopefully he can help me figure this out. I am not so sure if it is wired wrong, a poor design, or defective. He did agree with me over the phone that the full current shouldn't be running through R2 if it is a sense resistor, but I may have explained it wrong. Also, I just got another 3 pack of these in an order that I forgot even placing, so I hope I can find something to do with them :)

P.S. I am very thankfull for the pics you took with the light shining through it. It is probably an old trick, but it seemed ingenious to me!
 

VegasF6

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Well, just looking at it he said he wasn't able to tell much. Said he would take it home and play around with the o-scope. Did mention that the resistors aren't designed for that sort of load, but we know that already. The IC switching transistor mosfet thingy whatever it is should be handling the load. So that probably means wiring the emitter to it, probably the top left pin if holding it so the IC is on the bottom. Or, to both sides of the ceramic cap.

Also, looks like I may not get the chance to do a test run of that before next weekend :(

Sorry not to have more information.

Also, I could swear I found an older thread about this board and they didn't have much more luck efficiency wise, though I can't seem to find it now. In this thread, I think they were using a lithium cell to begin with, and were actually happy with the output, but the draw looked way too high to me.
 

VegasF6

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Well, I couldn't get this out of my head and have been looking it over some more. If I could find a data sheet for this IC it would be easy, but since I can't, here is another guess.

Lets assume the IC has 6 pins (well it does) and the one at the top left is 1, top right is 3, bottom left is 4, and bottom right is 6.

I think pin 6 is the ground circuit, and if you notice the small lead that is to the right of the IC that doesn't go anywhere really, I think that is your - emitter hookup. I tested resistance to the pin from that spot and it is pretty much a direct connection.

I think pin 3 is the mosfet switching side of the IC and it controls power to the inductor. After passing through the inductor, you can see it goes to the tiny filter cap that is to the right of the large diode, and then it comes out to the + point that you used.

I think pin 4 is the sensing pin. As far as I can tell, it comes out, goes to an empty pad for another diode that wasn't used, goes into R2, then R3 and finally to ground. Just to sample the current being drawn apparently.

Power comes in where the through hole is in the center. It then passes through the brown ceramic cap for some reason I can't imagine, maybe it is designed that way if for some reason you have a dirty power source? It then goes to the right into the diode, comes out of the diode, into pin 2 to power the chip. It also passes into R3 at the same time. From R3 into seems to go into pin 1 for whatever reason.

And finaly pin 5 appears to be unused, but it test with no resistance from pin 2, I think it goes straight through.

If you look at the picture Koala99 uploaded on the sales page for this item, on the old design, it appears that he is recomending hooking - to pin 4 and positive to pin 6. Well, pin 6 should be fine, but I believe by using pin 4 for his positive lead, he is hooking it up exactly the same way you did. I think the positive needs to be attached after the inductor, and after the filter cap, which on the old circuit would probably be the other side of the yellow cap at the bottom. I don't think that would really change the efficiency any, but it smooths out the output and should help with any flickering.

If you get around to changing the 1 lead for the negative to either pin 6 or the solder point above and to the right I would love to hear your results!
 

koala

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I copied and posted the wiring from a Nuwai/Gentos? light that I have. I tried to look for the datasheet as well but no fruit.

VegasF6 - lets hope your dad could give us some directions. Very interesting.
 
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rizky_p

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Interesting indeed. I'll try the solution you mentioned.

thanks

Well, I couldn't get this out of my head and have been looking it over some more. If I could find a data sheet for this IC it would be easy, but since I can't, here is another guess.

Lets assume the IC has 6 pins (well it does) and the one at the top left is 1, top right is 3, bottom left is 4, and bottom right is 6.

I think pin 6 is the ground circuit, and if you notice the small lead that is to the right of the IC that doesn't go anywhere really, I think that is your - emitter hookup. I tested resistance to the pin from that spot and it is pretty much a direct connection.

I think pin 3 is the mosfet switching side of the IC and it controls power to the inductor. After passing through the inductor, you can see it goes to the tiny filter cap that is to the right of the large diode, and then it comes out to the + point that you used.

I think pin 4 is the sensing pin. As far as I can tell, it comes out, goes to an empty pad for another diode that wasn't used, goes into R2, then R3 and finally to ground. Just to sample the current being drawn apparently.

Power comes in where the through hole is in the center. It then passes through the brown ceramic cap for some reason I can't imagine, maybe it is designed that way if for some reason you have a dirty power source? It then goes to the right into the diode, comes out of the diode, into pin 2 to power the chip. It also passes into R3 at the same time. From R3 into seems to go into pin 1 for whatever reason.

And finaly pin 5 appears to be unused, but it test with no resistance from pin 2, I think it goes straight through.

If you look at the picture Koala99 uploaded on the sales page for this item, on the old design, it appears that he is recomending hooking - to pin 4 and positive to pin 6. Well, pin 6 should be fine, but I believe by using pin 4 for his positive lead, he is hooking it up exactly the same way you did. I think the positive needs to be attached after the inductor, and after the filter cap, which on the old circuit would probably be the other side of the yellow cap at the bottom. I don't think that would really change the efficiency any, but it smooths out the output and should help with any flickering.

If you get around to changing the 1 lead for the negative to either pin 6 or the solder point above and to the right I would love to hear your results!
 

CampingLED

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Well, I couldn't get this out of my head and have been looking it over some more. If I could find a data sheet for this IC it would be easy, but since I can't, here is another guess.

Lets assume the IC has 6 pins (well it does) and the one at the top left is 1, top right is 3, bottom left is 4, and bottom right is 6.

I think pin 6 is the ground circuit, and if you notice the small lead that is to the right of the IC that doesn't go anywhere really, I think that is your - emitter hookup. I tested resistance to the pin from that spot and it is pretty much a direct connection.

I think pin 3 is the mosfet switching side of the IC and it controls power to the inductor. After passing through the inductor, you can see it goes to the tiny filter cap that is to the right of the large diode, and then it comes out to the + point that you used.

I think pin 4 is the sensing pin. As far as I can tell, it comes out, goes to an empty pad for another diode that wasn't used, goes into R2, then R3 and finally to ground. Just to sample the current being drawn apparently.

Power comes in where the through hole is in the center. It then passes through the brown ceramic cap for some reason I can't imagine, maybe it is designed that way if for some reason you have a dirty power source? It then goes to the right into the diode, comes out of the diode, into pin 2 to power the chip. It also passes into R3 at the same time. From R3 into seems to go into pin 1 for whatever reason.

And finaly pin 5 appears to be unused, but it test with no resistance from pin 2, I think it goes straight through.

If you look at the picture Koala99 uploaded on the sales page for this item, on the old design, it appears that he is recomending hooking - to pin 4 and positive to pin 6. Well, pin 6 should be fine, but I believe by using pin 4 for his positive lead, he is hooking it up exactly the same way you did. I think the positive needs to be attached after the inductor, and after the filter cap, which on the old circuit would probably be the other side of the yellow cap at the bottom. I don't think that would really change the efficiency any, but it smooths out the output and should help with any flickering.

If you get around to changing the 1 lead for the negative to either pin 6 or the solder point above and to the right I would love to hear your results!

Just need to confirm that I am not reading your message incorrectly. At some stages you refer to pin 6 as the negative, but also mention that Koala99 hooked his positive to pin 6.

When I studied the pics on DX my understanding of the old circuit is as follows:
- Pin 4 is the negative of the LED
- Pin 5 and Pin 6 connected to each other and to positive of LED
- The old circuits have two versions of the 2106F, 0731/20 (same as new one) and 0623/20. Not sure what the difference is.

My best guess on the new circuit:
- Little connection on Pin 6 to positive of LED (not negative)
- Either Pin 4 or the connection between R1 & R2 to negative of LED. You are currently using the one between R1 & R2.

Start by moving your LED red wire to the little connection on Pin 6.

I must confess that I have not done your detailed analysis of the other components like you did.
 

CampingLED

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I know this is alittle off topic, but do not want to start a new thread. Will these circuits drive a Rebel LED well or is the low Vf (3.15V) of the Rebel a problem. I have a flashlight that is not performing well and suspect the circuit. Will also be nice if it can also accept 14500's in future.
 

Tohuwabohu

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I ordered some of these drivers too. They were shipped a few days ago but did not yet arrive. So I only have your pictures as information and can not do my own research/testing.

Well, I couldn't get this out of my head and have been looking it over some more. If I could find a data sheet for this IC it would be easy, but since I can't, here is another guess.

Lets assume the IC has 6 pins (well it does) and the one at the top left is 1, top right is 3, bottom left is 4, and bottom right is 6.

I think pin 6 is the ground circuit, and if you notice the small lead that is to the right of the IC that doesn't go anywhere really, I think that is your - emitter hookup. I tested resistance to the pin from that spot and it is pretty much a direct connection.

I think pin 3 is the mosfet switching side of the IC and it controls power to the inductor. After passing through the inductor, you can see it goes to the tiny filter cap that is to the right of the large diode, and then it comes out to the + point that you used.
Current does not pass through a capacitor (at least DC doesn't). I think the small device on the right is a diode, the larger black one (labeled 100 6V) is a capacitor.

I think pin 4 is the sensing pin. As far as I can tell, it comes out, goes to an empty pad for another diode that wasn't used, goes into R2, then R3 and finally to ground. Just to sample the current being drawn apparently.

Power comes in where the through hole is in the center. It then passes through the brown ceramic cap for some reason I can't imagine, maybe it is designed that way if for some reason you have a dirty power source? It then goes to the right into the diode, comes out of the diode, into pin 2 to power the chip. It also passes into R3 at the same time. From R3 into seems to go into pin 1 for whatever reason.
Again, current does not flow through a capacitor. I think the brown ceramic cap smoothes output current, the big black one input current (it is connected parallel to the battery).

And finaly pin 5 appears to be unused, but it test with no resistance from pin 2, I think it goes straight through.

If you look at the picture Koala99 uploaded on the sales page for this item, on the old design, it appears that he is recomending hooking - to pin 4 and positive to pin 6. Well, pin 6 should be fine, but I believe by using pin 4 for his positive lead, he is hooking it up exactly the same way you did. I think the positive needs to be attached after the inductor, and after the filter cap, which on the old circuit would probably be the other side of the yellow cap at the bottom. I don't think that would really change the efficiency any, but it smooths out the output and should help with any flickering.

If you get around to changing the 1 lead for the negative to either pin 6 or the solder point above and to the right I would love to hear your results!
I'm not sure if the old design can be used as a reference to the new one, it seems to be completely different.


If the technical data on the dx-website is correct (1.5V~4.2V Input, 3.7V Output) the driver should be a buck-boost converter http://en.wikipedia.org/wiki/Buck-boost_converter. This means that the polarity of the output voltage should be opposite to that of the input. So my first guess would be to connect the LED just the other way round as rizky_p did in post #2. But of course I am not sure if this is correct, I am just guessing. I think it would be safer to use a resistor than a LED to test this, 5ohm 2W should be a good choice.

Could one of you check the polarity of the small black diode?
Is the lower end of the inductor connected to ground? I can not see it in the images.
 

VegasF6

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I do want to make it clear up front I am no expert on this and am just theorizing out loud.

CampingLED: you are right, I did say pin 6 was negative, and now I am thinking I was wrong on that one.

Koala, can you tell us which pins you are referencing for your positive connection in your picture? Pin 5? Pin6? Or 5 and 6 bridged?

I have been trying to trace this out with my meter set for continiuty, but I am getting funny results and not really sure I am reading it right.

Tohuwabohu, it will be good to have someone with more electronics knowledge than me to chirp in on this one. What I have been trying to do is find another boost buck board to reference to get some idea how they work, as I can't imagine they are all that different. I hope that by referencing the old board I can at least see what they have in common for pinouts on the IC, I think the main difference is just other added components, but the function should be pretty much the same?

You are right about the small device on the right being a diode I guess, since it is labeled D1, hah. Again, I am a rookie at this.

Near as I can tell, the bottom of the inductor goes to positive. From other designs I have studied, they usually boost positive voltage, and perhaps go through a filter cap? Or so I thought, but you are mentioning a cap doesn't pass current, so that must be my mistake.

IF I am using the meter correctly, the anode of the small black diode points down towards the inductor.

The cathode end of the diode has no drop between it and the positive pad. There is also no resistance from the anode of the diode to the base of the inductor, nor any resistance from either the base of the inductor or the anode to pin 3 of the IC. Also, there is .4 ohms resistance from the positive connection on the bottom of the board to pin 3 (but my meter shows .4 ohms even when I dead short the leads, so that is zero??) . So, what does that mean?

Even if we can't get better results from this circuit, I really want to understand the path the current takes. So, if there is something I can do to help, IE if you need me to check something else on the board, feel free to ask.
 

koala

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Good News! it's a Boost chip.

I digged hard and found the datasheet in my harddrive :). (I uploaded it to filedropper because China webby are behind the great firewall they are so slow.)

Brothers who can read Chinese, please download the datasheet above and help translate. Thank you.!

Product page http://www.ic108.com.cn/ic108_Product_2418195.html (I'm guessing) The HT2106 is a clone of the popular Belling BL8532.

Here's what Google translator says about the chip...
2nltflu.gif


Chip Internal stuff...
2jeb9rc.gif

4h5pau.gif

25z7d3l.gif


Reference Circuit taken directly from the datasheet... pg.4
rkd9qf.gif
 
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VegasF6

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I think we need to revise our pins for further discussion, because there's no Pin 6 in the datasheet. :p:p:p

Well that's for sure, there are only 5 pins, and they are not even close to the order I had guessed them at either. I wonder should I just edit out the guesses I made in my post back near the beginning or leave them? I suppose it won't hurt for people to see my mistakes, just hope they aren't used for EVIL, bwaaaa haaa haa haaa (that's my evil laugh.)

Great job finding that. Now if someone with more knowledge can look at this circuit, we can see where we are. But it is looking like this is for low current applications only, huh? And either they have designed it way out of spec, or somehow we are just really overdriving it.

Can't wait to see what this will bring anyhow.
 
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