Easy OKR-T VV mod

[skipdashu]

Well I'm actually a fan of big buttons. You really don't need a NC switch, which tend to be kinda twitchy unless you get a very high quality one. And if I understand your intent, I don't think you need a resistor at all with that approach. You are just pulling the pin to ground, there is no real volts/current involved in either the on or off position (I think )

Read this carefully.


You can use a normal NO one. You can set it up just like the MV reg if that's the one you are referring to to.

Just pull the pin to ground with a resistor, many values will work, this will keep your reg off. Then come off the positive with your switch. Your pull down, though, has to be a value that in combination with your switch/positive that will allow enough current to the pin to meet the requirements above.

Say we want 1mA when the cells drop to 6.5V, using Ohm's Law I get 6.5k. Theoretically it would appear that when the cells drop below 6.5V 1mA will no longer be available and the reg should shut down. A good thing. But Mamu is using 10kΩ which even at 8V is only .8 mA, but it seems to work fine. Maybe my whole line of reasoning is incorrect.

Head over there for a peek.

http://www.e-cigarette-forum.com/fo...ena-vv-mod-denalis-lil-sis-step-step-how.html

U r right on the resistor on pin 1 ... was a leftover from trying to put +2v on it in an earlier failed project.

Gotta go re-read the rest.

PS: Ok, got it now, pin 1 to resistor to ground AND pin 1 to switch to B+.
PPS: But I do have 1 NC switch left, guess I'll save it for a backup to my Great Bites Tin 5v mod as I used one on a KA378R05 in it.

 

[skipdashu]

no-workie

Half soldered into a madvapes min-board, half on a bread board last night. Hoping you might be able to point me to what to check next.

In comment box on right I should have said that the LED lights when I'm measuring 4.x volts only.

I'm about to take the caps out and/or try to find something smaller for R2 in an act of desperation.

 

[skipdashu]

I wish the 14500's where more than 900mah.

From the battery forums I'd say they're really ~750mAh for Trustfire flames and a touch under that for Ultrafires. Strangely enough that's just what the AW blk/chromes are rated.

 

[WillyB]

From the battery forums I'd say they're really ~750mAh for Trustfire flames and a touch under that for Ultrafires. Strangely enough that's just what the AW blk/chromes are rated.

Not really. It's important to put things into how we use the cells.

Here's a UF14500.

That's a rather modest 800mA drain to 3V (a realistic cut-off) for ~ 592mAh. Now for us we will be asking them to do about 3 times that, ~ 2+A. That's a big hit for these I'd expect actual mAh to drop below ~500. This may be an application where IMRs are a better choice.

I'm a bit confused by your rather slick schematic and some of the notes.

If I was troubleshooting it I'd bypass your switch circuit and see if works that way. Just disconnect it from pin one and use your Master switch as a fire button for testing purposes. That should help pin point where the problem is.

 

[skipdashu]

Hello all, I have been reading all threads concerning the OKR-T6-W12C and have a couple of questions if you would not mind helping me out understand a few things.
1. What difference does it make if I use the on/off of pin1 or just use switch on Vin pin?
2. It appears to me from reading the threads some are using the W12EC calling it the standard W12C. Which this leads into my question. Is the only difference in the two is the pull down resistor in the W12EC and no resistor in the standard?
3. I order input and output capacitors and I am not sure if I should us them?
I sure I may have more questions later on but this will do for now. Will appreciate any and all help. Thanks

Using the control pin will also result in a lower idle current draw on the batteries.

Update: sorry, that was in relationship to just using the fire switch on Vout not Vin.

 

[skipdashu]

If I was troubleshooting it I'd bypass your switch circuit and see if works that way. Just disconnect it from pin one and use your Master switch as a fire button for testing purposes. That should help pin point where the problem is.

Good info and I'll try taking out the fire circuit in a few. Thanx, Skip

 

[skipdashu]

If I was troubleshooting it I'd bypass your switch circuit and see if works that way. Just disconnect it from pin one and use your Master switch as a fire button for testing purposes. That should help pin point where the problem is.

OK, removing the switch circuit and moving the LED from the output side to the input side and I now have voltage out that will vary. The range is a bit off but I'll go find bstedh's tables and check it against those. I don't know how much variance reg to reg there s/b but here's what I've got.

R4+R5 min = 214 ohms
R4+R5 max = 396 ohms

This is giving me an output voltage range of 2.75 thru 4.31 volts. I suspect I just need to swap out the 220 ohm R4 for a 330ohm but I'm a bit worried about why I appear to be off this much.

Once I get this sorted out I'll try putting R2, S2 and Z1 back into it

As it currently sits HERE.

 

[skipdashu]

With this regulator the lower the resistance the higher the voltage output.

I don't think you would ever want max resistance other than in some specialized circuit.

I only use the variable of one side. You could tie it in for protection but if it's broke its broke

The ohms range for the regulator is 200ohms for around 6V and 450ohms for around 3V so you want a minimum of 200ohms hence the resistor attached to the variable giving you an operating range from 200ohm to 400ohm or 450ohm depending on the value of the variable resistor you choose. Basically the resistor sets the lower end of your range.

Here is a pic of the table I used to figure out the resistance needed for this regulator. The 200ohm variable was not in stock when I ordered so I had to figure it with 500ohm hence the difference in circuit design from what is posted here.

Edit: I worded the values wrong but the table will make that clear =]
Edit: fixed

POOP! I must still have something wrong as I'm getting 2.75v @ 214 ohms and 4.31v @ 396 ohms.

Taking out the trimmer and putting some resistors on the bread board I get:

220 (measures 214) gives me 2.75v
220 + 220 gives me 5.25v
220 + 330 gives me 5.59v

Any ideas why?

Wait a minute... This is backwards! Off to double check this.

Yup, My output voltage goes up as my resistance goes up. ????

 

[Java_Az]

Here is the chart from the modules PDF. You should be getting a higher voltage out of it @ 214 ohms

Any ideas why?

best guess is it is not hooked up right easy to get this chip turned around. looking at the inductor side pin one is on the far right

 

[skipdashu]

Here is the chart from the modules PDF. You should be getting a higher voltage out of it @ 214 ohms

best guess is it is not hooked up right easy to get this chip turned around. looking at the inductor side pin one is on the far right

My first thought also but I'm using pin one as the far right looking at it from the top (the side with the big things on it) and I'm measuring output voltage from pin3 to pin4. trim on pin5 (the one I would've called pin 1) far left.

The other reason I think I have the right pins is I had a switching circuit on pin 1 but it's disconnected right now. When it was there my fire button thru the zener would turn it on / off.

There must be some other "duh!" going on here. Also if I hook a wired atty connection on the breadboard and screw in an atty my output voltage drops to something under 0.1v.

 

[WillyB]

This chart may be easier to use.

Shooting for ~230 total Ωs (measured, resistor with trimmer in series) should keep you in spec on the high side. There is really no need for 6V, especially using 14500s as the actual vapetime would be rather short.

Check your 220s you should be able to find one on the high side, your trimmer at 185 is a good thing actually

 

[Java_Az]

My first thought also but I'm using pin one as the far right looking at it from the top (the side with the big things on it) and I'm measuring output voltage from pin3 to pin4. trim on pin5 (the one I would've called pin 1) far left.

The other reason I think I have the right pins is I had a switching circuit on pin 1 but it's disconnected right now. When it was there my fire button thru the zener would turn it on / off.

There must be some other "duh!" going on here. Also if I hook a wired atty connection on the breadboard and screw in an atty my output voltage drops to something under 0.1v.

I was thinking you had the input and output switched around but it doesnt sound like it from what your saying. Looking at the last geda schematic you posted it should work wired like that. If your certain it is wired like that and you have tested for short circuits it must be a bad chip.

 

[skipdashu]

Well dudes (and dudettes) it is fixed. At least in this stripped down version. What was it you ask? Well that's a cross between an Elephant and a Rhino... also known as an 'Elliphino'. I squezzed my little mini-board between my finger and thumb while measuring some voltages with fixed resistors on pin 5 and they jumped. I tried a couple variations 220, 220+220 and a 330 and the voltages now seemed inverse of the resistance as it should be. I put the trim pot back in and all seems good 3.57 at the bottom 6.07 at the top (no load). Screwed a 1.25 ohm DC carto onto the batt connector (on the bread board still) and it vapes and voltage drop is now what seems normal.

I'm going to add the control pin enable/disable switch circuit back in and see what happens.

Skip

PS: I tried to wiggle everything on the board and I can't seem to make it jump anymore so I'm really at a loss. I'll go thru it again as it could be the connection between the reg and the mini-board but I had already checked them with the meter. Maybe there was a piece of something on the back side of the board that I inadvertently removed. I dunno.

PPS: I'd post a pic of this contraption but I don't wanna get sued when u fall off your chair and hurt ur self from laughing at my soldering.

PPPS: Last time I had a problem like this it WAS a bad connection between the regulator and the mini-board but that time I could measure the resistance jumping around between the pin and that row on the board.

 

[Java_Az]

Sounds like a bad connection or inadvertent short , reason I make my own PCB's for these modules since i dont like to bend the pins to get them to fit into a breadboard. I see you use geda schematic editor. not sure if you have gotten around to using the geda PCB designer but if you do and need the Footprint for this chip/ module let me know i can send it to you. I meant to make just a generic PCB design for this module awhile back and release it open source for all to use, but kinda got side tracked. Maybe i will whip one up this weekend and post it in here.

 

[skipdashu]

I went back and re-flowed where all 5 pins connect into the mini-board. Now trying to figure out how high I can go on R2 before the thing just stays on. 13K and 12K didn't work. I put 2 12Ks in parallel and that worked. Now I have a huge 2K power resistor in series with the two 12Ks in parallel (8K) and that works. I suspect Mamu was using a 10K for a reason. Time to go look on the Rat Shack as that's all that'll be open around here tomorrow. I'm actually surprised that this thing need this dropping resistor that low. The 5v things I used in the past you could use 100s of K on the enable/disable pin.

I got a better idea... instead of open sourcing the PCB file, create the board and watch me open source my wallet to you ;-)

I'm such a noob with gEDA it's not even funny and I've never created a pcb in my life. I found it in the repositories when I decided I needed to draw a picture that I could share. Does that rather nicely.

So, there are actually a couple of ya'll out there that could load up a .sch file instead of me taking screen shots of it!

Last time I worked in electronics we had big vacuum tubes and had figured out that you could heat a ham sandwich up on the feed horn of the antenna if you cranked it to point straight up in the air ;-) Thank you USAF.

Mostly a HUGE thanx to ya'll for giving me a hand with this.

Skip

PS: Local Rat Shack has 10Ks I have a pair of AW IMR 14500s that I'm running down to see when this thing decides they are too low and will not fire. At 7.25v no load / 6.7v loaded and it is still firing. Next up is to add back the V display and it's switching.

Updated the temp schematic HERE or .sch

 

[skipdashu]

WillyB,

I see what you're saying now. These tested to around 635mAh @ 2A.

 

[skipdashu]

It mostly depends on which voltage you would like to measure. If you are using the MV MM you have I believe 6 different measurements you can take. So you can measure each cell, cells combined, and atty output.

For basic output measurement you would go from battery negative to atty positive.

I don't suppose the MV MM rotates reading thru any pin with a voltage present all automajically, does it? Otherwise, what's the point if I have to put a complex switch in to do more than two voltages?

 

[Domtine]

After reading the entire thread or at least 90% of it, I've decided to embark on making a mod using the regulator.

Came up with the schematics using PCB Express. Hope that someone could proof read it for me. Don't wanna fry anything cos this regulator ain't cheap.

Don't worry as I already have the essential stuff like stripboards, extra flux, de-solder wicks and some soldering skills I've picked up working as a technician.

 

[skipdashu]

After reading the entire thread or at least 90% of it, I've decided to embark on making a mod using the regulator.

Came up with the schematics using PCB Express. Hope that someone could proof read it for me. Don't wanna fry anything cos this regulator ain't cheap.

Don't worry as I already have the essential stuff like stripboards, extra flux, de-solder wicks and some soldering skills I've picked up working as a technician.

View attachment 85226

I think D1 is backwards. Still looking at SW3.

ADD:
I am a bit uneasy about putting a switch on the high amp load line and don't see the purpose. If it's for meter switch take a look at THIS which uses a SPDT with center off that was sourced earlier in this or maybe the Dena vv thread. I've got an invoice around here someplace for it... online components, or mouser or all electronics.

 

[WillyB]

WillyB,

I see what you're saying now. These tested to around 635mAh @ 2A.

It did well @ 2A, but note most will not want to dag a cell down to 2.8V, even the 3V cut-off I mentioned (which now puts them <600mAh) may be a tad to low.

Found this comment interesting:

This battery has more capacity than specified, even at 1A load.

The China made Tenergy 14500s are rated at 800mAh.

I'd like to see someone add a protection circuit to a Sanyo 14500 as they list capacity at 840mAh.

With their 18650s both Tenergy and Sanyo's mAh ratings are quite accurate and top performers.