Soldering Tiny Phone Charger Wires

Have you got the LED round the right way.
Buy a cheap digital multimeter you can use it to check continuity, volts and current...

The most important thing when starting out in electronics (or just about anything) is simplicity. Prove the simple things work first. IMO there are too many fancy ICs used by people who don't understand the basics, when they'd learn more with a few discrete components.

Del

The LED is going the right way. I do have a multimeter, that's how I can tell no current is getting through the driver.. am wondering if I did something wrong on the other end or if the driver isn't getting enough power from the source somehow.

Like this...?

https://www.sparkfun.com/products/13716

Yep, that's the one..

GA

I think there's a clue in the original post:-

supplying 5 volts. (The LED needs 3.4, the driver needs 2).

Okay, this was a silly mistake. Thanks for helping me catch it though!

Thanks Rixter, I feel a little silly but yep, there it is plain as day!

There is a possibility you now have a dead LED. The voltage vs current curve (I-V) for an LED is a very non-linear curve. To protect the LED from being over driven a current limiting device (resistor) is typically in series with the LED.

That 5 volt phone charger may produce considerably more voltage when not connected to the battery it is designed to charge. If you did not have a current limiter then the LED may be dead.

GA

My thoughts too.....

There could be a couple things wrong. Here is where I'd start troubleshooting:

1. Check for cold solder joints. Use your ohmmeter to test for conductivity on both sides of the solder joint.

2. If all solder joints are good, then you may have burned out the diode (too much heat). Check resistance both directions (+ to - and - to +). You should have 0 Ohms one way and an open circuit the other way.

3. If the diode is good, then check your power supply. When you turn the supply on, check the voltage at the output to make sure you have 5V. The power supply may not provide enough power, so when a load is placed on the supply, you could get a large voltage drop - not enough voltage to run the circuit.

Soldering tip: Here's what I learned to do when soldering. Some people try to solder by putting the solder on the tip of the iron, then trying to get the solder from the iron to the wires. This results in cold solder joints - not a good thing. Try this instead. Tin the tip of the soldering iron with a thin coat of solder. Then touch the iron to the wire and let it heat up. Touch the solder to the wire (not the iron) and when it begins to melt, pull the iron away from the wire. You should get a nice and shiny solder joint. If it doesn't flow well, touch the iron to the wire, but don't get it so hot that the solder loses it's shine - you've overcooked the solder and you should clean it and start over.

If you're soldering something that can't take too much heat, then use a heat sink between the soldering iron and the component. You can use an alligator clip or some other sort of clip that's made of metal. The heat will transfer from the wire to the heat sink and not to the component. Always use rosin core solder or the new water based version. NEVER use plumbing solder on electronics - it'll damage the wire, board and components.

I hope this helps.

Good info, but you did not mention thermal units! Also, I do not know anything about mapp gas....so I turned to Wiki....

In fact its not that hot or its hotter- 2,020 °C (3,670 °F) depending upon which units you actually meant!!! You are right that you can get "nearer", but is it worth it?

In fact a great difference with either units to your post, but not really that much hotter than propane...

According to Wiki.....

You're right, I meant °C but, having looked at Wiki again I see that they quote 2020°C in air & 2925°C in oxygen. I was looking at the wrong numbers.

LOL!!!

Nobody got hurt and you meant well!!

I think MAPP gas set ups (at least here in the States) are meant for light brazing work, whilst propane torches are used for soldering work on large copper (or copper or brass plumbing fixtures).

I have brazed steel with propane and silver soldered copper as well.....

Additional ideas

Recently had need to check phone charger for voltage output. While it was nominal 5V DC, it was more like a full wave rectified that peaked at 5V.

Your problem may be in the selection of the power supply. Check that for AC ripple and DC level.)

Suggest try your assembled unit with a small DC battery stack (4 X AAA in series) and see if that works.

The other possibility is that in your soldering process, the IC has been overheated and failed.

The final option is that the LED leads have moved inside the capsule and are shorted. This is surprisingly easy to happen. You can check this by measuring the current through the LED. If there is current and no light = internal short.

We used to process around 30,000 through hole LEDs per day for automotive lamp assemblies.

Very simple: you are burning up the LED in the attempt to solder leads to it. Just solder the leads to a socket or stick them in a breadboard and then insert the LED, see it that works for ya. Otherwise, chunk that LED and insert a new one into your fun board.

Just my $.02 in the pot. For some reason many wall warts are made with Litz wire. Makes it a real pain to solder since each strand is covered with what often seems to be bullet proof insulation. Back in the old days we used to burn the insulation off with a match then clean the wire with emery cloth before soldering. Try to find someone with a match these days...

There are lots of "how to" videos on YouTube making 5V or 12V soldering irons like LED lights, speaker wires, and other small projects like Mini Portable USB Soldering Iron With 5 Volt Mobile Charger. But you can check the video where you come to know the things required to Make Mini Portable USB Soldering Iron With 5 Volt Mobile Charger, Pencil Homemade.
https://www.youtube.com/watch?v=EcSpOi-dYd0