How to make a 5V mod with a TI regulator.

[DenniZ]

I'm re-posting the tutorial found at the end of the following thread, to give it some more visibility to those who may be interested in it. http://www.e-cigarette-forum.com/forum/battery-mods/97743-what-ti-voltage-regulator-use-5v-mod.html


***Please read the whole tutorial before beginning***
Also read up and watch a video of how to solder if you are new/less then proficient at soldering. Since this is a mock build, I am not trimming down my leads or isolating the heat-sink of the Regulator (the metal tab with the screw hole in it), you will want to do both of these things to prevent headaches later. trim down the metal pins to what you need, wrap them up individually and also heat-shrink or electrical tape the back and metallic sides of the regulator to prevent short circuits.
#1

Tools you'll need:
Wire cutters
Pliers/Multi-tool
Soldering Iron + Solder

Optional tool:
Helping Hands

Components:
Voltage regulator
Momentary switch (SPST) 3 amp 125v
Wire
Lithium batteries ( I use only protected 14500)
Electrical Tape

Optional Components:
Light Emitting Diode (LED)
Printed Circuit Board (PCB)

Optional RECOMMENDED
Master ON/OFF switch
Heat-shrink Tubing

#2
OK... Lets get started. Place Heat-shrink tubing on each wire prior to making a solder connection, or Electrical tape them well.

#3
Pin polarity/function on the TI REGULATOR

#4
(+) Voltage in, left most on a right-side-up Regulator with pins facing you.

#5
(-) Ground, Middle Pin

#6
(+) Voltage out, Right-most pin with Regulator facing up, pins facing down.

#7
How it looks wired up without an LED, If you are using an led, there should be one more ground (middle pin) and one more voltage out, (right pin).

#8
If you are using a battery box with a master on/off switch, this is how it should be wired for the (+) voltage in. Note how the (+) Voltage in passes through the momentary switch before entering the regulator

#9
This is how the (-) ground would wire into the master on/off of the battery box. If you are using another enclosure but still want a master on/off to shut down the entire device, solder it between these two wires.

#10
One of the ground wires (-) from the middle pin needs to connect to the battery connector, Note how it is soldered to the OUTSIDE of the connector.

#11
This is a close-up of the (-) ground wire soldered in #10

#12
This is a the (+ )voltage out.

#13
Close up of #12, note how it attaches to the center of the battery connector Make sure it DOESN'T touch the side or you will have a short circuit

#14
If you are not using an LED, skip to #17 to check your wiring before testing your new PV.
Optional LED polarity, I didn't cut the LED leads down for this instructional, but you will want to trim them down. Keep the long end slightly longer so you can tell which is which. The LED will only function if the polarity is correct. It is important to shrink wrap or electrical tape the leads to the LED, failure to do so will result in a short circuit if and when they do touch.

#15
Connect the additional wire you added to the (-) ground in step #7 to the SHORT (-) end of the LED

#16
Connect the additional wire you added to the (+) Voltage out in step #7 to the long end of the LED.

#17
This is how everything should connect together. Make sure you trace out each wire and make sure your optional Master On/off switch is in the on position before test firing your new PV.
CONGRATS AND ENJOY, -DEE

 

[WillyB]

Very nice and easy to understand guide with great pics. The only thing I would add would be a resistor to limit the current to the LED. Most of the ones we use are made for about 20mA of current. In general, common values of 220, 330 and 470Ω all will work. The value you choose will also determine the brightness. The resistor can go on either the positive or negative leg.

 

[DenniZ]

Excellent suggestion WillyB,
I haven't had an LED burn out yet but I have noticed that they get REALLY hot, I was hoping to find a fix for that problem so thanks a million.

 

[Quexos]

Thanks. Very nice.

 

[Distorted.Clarity]

wow!
now thats what i call a good tutorial!
i just snagged 5 of those from TI.

 

[MuddyBears]

so i guess you don't need to use a 10uf cap with this reg since it is fixed?

 

[BababooeyHTJ]

I didn't know that it was that easy to build a 5v box mod. Thanks

 

[bigblue30]

so i guess you don't need to use a 10uf cap with this reg since it is fixed?

You do not "have" to use that cap with the fixed or variable and it will work. TI highly "recommends" that you do.

They help to take some of the "shock" from the chip when you throw the switch. It help the chip live longer.

 

[MuddyBears]

You do not "have" to use that cap with the fixed or variable and it will work. TI highly "recommends" that you do.

They help to take some of the "shock" from the chip when you throw the switch. It help the chip live longer.

thanks blue.

 

[jharres]

Which capacitor should I buy to use with the TI regulator? Also, I assume it's placed inline before the input on the regulator, is this correct?

 

[derek88]

These seem like they would get the job done unless its some other type of capacitor your referring to.

http://www.madvapes.com/10-uf-10v-Multi-layer-capacitor_p_2144.html

 

[bigblue30]

These seem like they would get the job done unless its some other type of capacitor your referring to.

10 uf 10v Multi layer capacitor

They look correct. I am not sure they are Tantalum. They do not say.

I know the ones I ordered from here are. With free shipping.

10 uF 10 Volt Tantalum Capacitor - (10 each) - eBay (item 380191086056 end time Jul-21-10 18:50:34 PDT)

 

[Shai]

Hey all, I plan on making this mod, already have the TI regulator. Thanks to DenniZ for the easy tutorial with a regulator that doesn't have 4 leads like some of the more popular mod walk throughs. Just so I understand what I'm doing would someone mind looking at this schematic I drew? I'm a little confused about how the LED works into this with the resistor. I assume it's off by itself as pictured since we don't want the resistor inline with the rest of the circuit?

 

[bigblue30]

Shai,

Take a look at my schmatic in the first post.

http://www.e-cigarette-forum.com/forum/battery-mods/102419-adjustable-voltage-box-mod.html

Your chip only has 3 pins so you do not have pin 2 or pin 4 like on mine, but you should connect your LED like mine. The one on the left is the power on led and the one on the right is the fire LED.

From your picture you are hooking up the "fire" LED. The LED and resistor goes from your pin 3 to ground just like the atty.

 

[Shai]

Your schematic is a little difficult for me to understand though I did look up all the symbols and know what is what. If I understand what you're indicating is that the LED should be moved outside the regulator's loop?

 

[bigblue30]

Your schematic is a little difficult for me to understand though I did look up all the symbols and know what is what. If I understand what you're indicating is that the LED should be moved outside the regulator's loop?

I will use the one you have. I hope it is easier to understand:

Yes the LED goes from your pin 3 (vout) to ground (-battery). AND the capacitor can not be wired like you have it (+ side has to go to +). The capacitor goes from pin 1 (vin) to Ground (-battery)

Also when you draw a battery the "long" side is the + side.

I hope this help. If not let me know.

 

[Shai]

Thanks for the help Bigblue. I'll post pics when I get all the stuff and build it. Probably won't be pretty

 

[bigblue30]

No problem, Any time you a question feel free to ask.

 

[jfdpl686]

big, you're showing the cap with +/- Aren't caps bidirectionals? How do I check which is +?

Second question. I will make a mod but I want to use a main on/off switch.
So I'm thinknig of getting the parts from a 2AA box.
So, from the battery's + i connect the main on/off, then the button, then the cap, then Vin.
From Vout I go to the Atty.
From battery's - I go to the cap, then atty then ground of the regulator.
Right?

 

[DenniZ]

big, you're showing the cap with +/- Aren't caps bidirectionals? How do I check which is +?

Second question. I will make a mod but I want to use a main on/off switch.
So I'm thinknig of getting the parts from a 2AA box.
So, from the battery's + i connect the main on/off, then the button, then the cap, then Vin.
From Vout I go to the Atty.
From battery's - I go to the cap, then atty then ground of the regulator.
Right?

Sorry I've been absent so long, been caught up with personal life.

For Q#1 here is a link, I'm assuming you are using a tantalum cap, so scroll down to pic# 5, and read the section and the caption. Capacitors
Working with different types and sizes of caps take a certain degree of knowledge so as not to damage the component and potentially hurt yourself. From my prior experience working with very large caps such as those used in car audio, extreme care must be taken to slowly charge them up and discharge them prior to removal, I typically used a small incandescent light bulb. This won't be an issue using the small caps that you are using, but tantalum caps do have polarity, so you should connect them correctly to avoid a fiasco.

For Q#2 I like to place my Master kill switch as the final component before the negative terminal of the batteries. If any more experienced hobbyists have any input feel free to drop some knowledge on us. I place the kill switch here because I wanted to make this instructional to be easy to understand and be easily expandable. This way if someone wanted to throw in addons like caps, they would be able to throw the kill switch and know for certain that absolutely no energy, including any stored inside cap(s) would be able to flow through. On a side note, I've heard of some people using these dinky switches in place of the momentary switch and I advise against it since they aren't rated for this application and the arcing that will take place at the moment of throwing the switch will quickly ruin it.