OKL2-T/20 100 Watts - 20 Amps

[Breaktru]

I got this email over a week ago and forgot to post about it.

MuRata has a 100 Watt, 20 Amp DC-DC Converter. SEE THIS
I requested a sample and received a conformation back on 2/5/14. Haven't heard anything since then.

It's 3 times longer than the OKR-T/10 but smaller than the Naos Raptor

OKR-T/10 dimensions: 10.4 x 16.5 x 7.62 mm
OTL2-T/20 dimensions: 33.02 x 13.46 x 8.75 mm
Naos Raptor dimensions: 36.8 mm x 15.5 mm x 9.2 mm

[CraigHB]

Interesting part.  It's designed to be surface mounted on a host PCB so it uses a one sided PCB.  That gives it a bigger profile as well as the bigger switches and larger inductor it uses to support the higher currents.  The inductor stands off above the control circuits below it which is an economical use of space.  It's got onboard input capacitors which is another advantage over the Raptor. 

I noticed there's two part numbers for that, one with negative control logic and one with postive control logic. 

Generally speaking, those guys make really good regulator modules.

[Breaktru]

What do you think about soldering wires to the Pin Pads instead of using a PCB Craig?

[CraigHB]

It uses the same kind of soldering pad you see on things like surface mount LEDs.  Those are pretty tough, but I suppose it would be possible for the pads to rip out under stress with heavy wires attached to them.  You probably will want to apply a blob of epoxy or silicone glue after soldering to provide some strain relief.  Of course, that makes it a permanent installation, but probably not an issue.  Depends on the pads though, if they're on a copper fill which they would probably have to be for the inputs and outpus, they'll be plenty strong enough.

[mamu]

Murata also has a 30A, 125W smd dc-dc converter: LSM2-T/30-D12R-C

That one and the 20A one I nixed for the less than 6v output.  Murata should be able to give us 6v output like the Raptor.  You can push it to 6v by changing the resister, but I don't like to do that.

[Breaktru]

Crazy stuff mamu. Thanks for the posting. I probably will never use it but who knows?

[CraigHB]

Murata should be able to give us 6v output like the Raptor.  You can push it to 6v by changing the resister, but I don't like to do that.

They design these parts to be used as power supplies for other electronics.  That stuff typically runs at 5V or below so they design the limit a little above that.  It's a failing with a lot of these regulator modules for our application.

You can overdrive the regulator, but you run the risk of failure.  You can look at absolute maximums in the data sheet and that will give you an idea.  When they say absolute maximum, they mean absolute maximum.  The part will fry if you exceed those specs.

[Visus]

I also had a sample request acknowledged here's my email response:

Thanks for your interest in Murata Power Solutions products.
 
Unfortunately, we can’t provide free samples for your anticipated production volume. However, these parts are readily available at a modest price from our catalog distributor, Digi-Key. Please follow the links below for more information on each of the parts.
 

I had 500-5000 as possible future volume

 

[Breaktru]

Still no word yet on my sample request. At the time the part was NOT available from distributors

[Visus]

Still no word yet on my sample request. At the time the part was NOT available from distributors

It was not for that part,  just the basics t6-10

Because its new they might do the sample request hopefully. 

[Madyicstik]

Murata also has a 30A, 125W smd dc-dc converter: LSM2-T/30-D12R-C

That one and the 20A one I nixed for the less than 6v output.  Murata should be able to give us 6v output like the Raptor.  You can push it to 6v by changing the resister, but I don't like to do that.

Mamu, is it possible to get a schematic diagram on where to put resistors and switches on our ecig applications? Id love to try this, currently have 3 okr and ti build based on your tuts and breaktru's and i think i have the modding bug.

[mamu]

Breaktru has a wiring diagram for Murata's OKR-T10 in his OKR thread, so use that as a guide as these Murata converters are all essentially wired the same with on/off control, Vin, Gnd, Vout, and Trim.  The only difference might be the converter's equation to calculate what trimmer and resister you need to get the output voltage range, and what pull down resister you need if using the on/off control.

Or if you want to work with the 20A 120W Naos Raptor board, see my thread tinkering with the Naos Raptor - the wiring diagram is in post #16.

The Raptor is rather a big converter though compared to these smd Murata converters, so need a bigger case.

[Madyicstik]

If i understand it correctly, calculating the resistor value and trimmer value , we are shooting for max output of 6v for LSM2-T/30-D12R-C correct? So if we try to bring the murata module down to 6v max would give us the same out put as an okr-T-10 at 6v?  Which will pretty much defeat the purpose of running LSM2-T/30-D12R-C? Or will we still be able to use the 30A/120 watts at 6v?


Im pretty experienced with modding(putting thing together part) But im new to the whole electronics thing like calculations of value s of various elect components.

[Breaktru]

Mady, the LSM2-T/30-D12R-C that you mentioned requires a min Input voltage of 8.3v

[mamu]

Where did you get the 8.3v, breaktru?

From the datasheet:

This tiny converter is ideal for applications with an input range of 6 to 14 Volts DC.

[Breaktru]

The Digikey specs are wrong --> Digikey

The datasheet shows input 6v-14v

[mamu]

If i understand it correctly, calculating the resistor value and trimmer value , we are shooting for max output of 6v for LSM2-T/30-D12R-C correct? So if we try to bring the murata module down to 6v max would give us the same out put as an okr-T-10 at 6v?  Which will pretty much defeat the purpose of running LSM2-T/30-D12R-C? Or will we still be able to use the 30A/120 watts at 6v?


Im pretty experienced with modding(putting thing together part) But im new to the whole electronics thing like calculations of value s of various elect components.

The max output of this converter is 5v, not 6v, and at that voltage the max current is 25A, not 30A.

I'm not sure what you're asking with defeating the purpose? The T10 max is 50W and 10A.  The LSM2 is 120W and 30A.

Calculate Ohms Law with W = V (squared) / R and also Amps with I = V / R

Say you want to run a 0.3 ohm atty at 4v or 4.5v:

4v (squared) / 0.3 ohms = 53W (and V / R = 13A)
4.5v (squared) / 0.3 ohms = 68W (and V / R = 15A)

The LSM2 can handle that higher power and higher amps, the T10 can't.

I don't vape at those watts and amps, but I hear some do.

[mamu]

The Digikey specs are wrong --> Digikey

The datasheet shows input 6v-14v

That's unusual for Digikey to get it wrong.  Mouser is usually the one to give inaccurate specs.

[Madyicstik]

Apologies, I've mixed up my numbers,  I  assumed that both modules will  give the give the same output at the same max volatge. I get it now, I've seen your naos raptor build and I think ill try my hands on that. You and breaktru are such great sources of valuable information.

[mamu]

Running uber low ohms, 5v max with this converter will give you the power and amps you're looking for.  But then that 5v max limits those of us who do normal ohms and want that 6v and don't need the super high watts or amps.

[CraigHB]

If i understand it correctly, calculating the resistor value and trimmer value , we are shooting for max output of 6v for LSM2-T/30-D12R-C correct?

Where did you come up with that part number?  That's an obsolete part.  We're talking about the OKL2-T/20 here.  That one can do 100W and 20A which should be adequate for even the lowest of the sub-Ohm builds.  I took a look at that data sheet again to see if I could get any indication as to overdriving the regulator to 6V.  I don't see anything that says it can't be done other than a footnote to observe maximal output power limits.  So, it may be possible to get 6V out of the regulator without issue.

[mamu]

Where did you come up with that part number?  That's an obsolete part.  We're talking about the OKL2-T/20 here.  That one can do 100W and 20A which should be adequate for even the lowest of the sub-Ohm builds.  I took a look at that data sheet again to see if I could get any indication as to overdriving the regulator to 6V.  I don't see anything that says it can't be done other than a footnote to observe maximal output power limits.  So, it may be possible to get 6V out of the regulator without issue.

I posted that part number (see post #4) as another example of Murata's high watts high amps converters.  It's not obsolete.  Mouser is out of stock, but digikey has it in stock.

And now you confuse me by saying it may be possible to get 6v without issue when previously you said in this thread you run the risk of failure when I mentioned I don't like to run out of spec and push it to 6v.   Of course, I reckon anything's possible but why chance it?

I know a modder who set the resister to push 6.5v - 7v from the OKR-T10 and is selling mods to people with that out of spec max and is now complaining how unreliable the T10 is because of the high failure rate.  Stuff like that makes me mad as it's not only irresponsible, but to blame the manufacturer for it when the modder is pushing the converter out of spec is just stupid.

But yeah, running out of spec just doesn't make sense to me - why take the chance for increased stress and failure?  Plus if there are converters that have the specs you need - like 6v - why not use them instead of a converter that you push higher than the manufacturer intended?

[Madyicstik]

Apologies if I caused any confusion, and if the thread got side tracked. I was just inquiring. Mamu is right, digi key do have them in stock.

I'm going back to my silent mode and just read up on info here.

[mamu]

My goodness, there's no reason to go into silent mode or apologize.

There's some of this stuff with modding I would call the gray zone as it's not always black and white or there may be exceptions.  In the end, we make our own informed decisions and build our mods how we want and what we are comfortable with. 

And we all have our opinions on what's what - my opinion doesn't make me right or another's opinion doesn't make them right, it's just opinions is all. 

I don't run a converter above or below manufacturer stated specs for fear of component stress or failure or for safety reasons, but so what - that's just me and what I'm comfortable with.  I know some manufacturers under spec their converters so others may be aok with running it out of spec, but so what - that's their decision to do so.  However, it's not right to blame the manufacturer if the converter fails due to running it above max spec as that one modder is doing.  I have high reliability with my mods using the OKR.  I made close to 200 mods with the T6 and over these past 3 years I've only had 2 board failures.

We should be able to discuss how we feel about some of these things.  Plus, it would be pretty boring if all of us agreed on everything.   

[Madyicstik]

I agree, i think this would be one of the reason why TI under rate some of their specs.(just guessing) just incase someone decides to go over the written spec, at least theres a little bit of buffer. But either way this forum is great source of info. As a matter of fact, this is where i learned how to build mods (and vapers forum)


Keep up the good work, i hope someday i can contribute to the wealth of information that we have here.

[Visus]

Ti chips are awesome

Have no complaining whatsoever
Obviously the OKR are awesome as well if used properly.

Nice manufacturing build stat mamu

[CraigHB]

I posted that part number (see post #4) as another example of Murata's high watts high amps converters.  It's not obsolete.  Mouser is out of stock, but digikey has it in stock.

Oops, should open my eyes instead of my mouth.  Anyway the data sheet for that part says, "not recommended for new designs" stamped in bold letters on the front page.  That means the part is no longer in production.  Doesn't mean you shouldn't use it, but it's not a good idea to use an obsolete part since it might not be available if you want to build the design some time in the future.  Probably for a basic regulated mod it's not a big deal, just use a suitable substitute, but for more involved designs, it can be a problem. 

And now you confuse me by saying it may be possible to get 6v without issue when previously you said in this thread you run the risk of failure when I mentioned I don't like to run out of spec and push it to 6v.   Of course, I reckon anything's possible but why chance it?

Well, it may be possible, but yeah, not recommended.  I'm only saying that the data sheet does not directly indicate a limitation there so it may be possible to overdrive the regulator, but the risk of failure still stands.  Running it at 6V is still out of spec.

I know a modder who set the resister to push 6.5v - 7v from the OKR-T10 and is selling mods to people with that out of spec max and is now complaining how unreliable the T10 is because of the high failure rate.  Stuff like that makes me mad as it's not only irresponsible, but to blame the manufacturer for it when the modder is pushing the converter out of spec is just stupid.

I can understand that.  It's not fair for a part to get a bad reputation because of people running it beyond its design limits.  It's actually kind of negligent for someone offer a product for public sale that uses parts running out of spec.

But yeah, running out of spec just doesn't make sense to me - why take the chance for increased stress and failure?  Plus if there are converters that have the specs you need - like 6v - why not use them instead of a converter that you push higher than the manufacturer intended?

No argument, I agree there.  Personally, I've not once built something that runs parts beyond their design limits, even for my own use.  You have to rely on a margin of tolerance for that and in some cases, there isn't much to begin with.  Other times there's a lot so it's pretty much a crap shoot.

[Visus]

Its funny at Ti depending on who you talk to, what info you can gather.

I spoke to the guy who built the 08100 chip he was livid about it being used in e cigs as he said, "if you adjust voltages in less than 3 millisecs while the unit is powered it will eventually possibly dramatically fail."  In our use, we usually do not change volts when under power so that is not a huge concern unless using a digital pot.   Then I spoke to another engineer who told me that the 4050c is underrated by a huge margin how big that margin is he didnt exactly say but he did infer it has been tested up to 10A.  Thats an absolutely enormous jump from stated max limit of  2.4amps.  It must be its efficiency is so far in the crapper at higher amps and/or becomes unstable.

I would comfortably sell a 4050c with a lipo battery, if the amp rate is too high it just wont fire..  It buzzes saying, hell no un un try again..
I am going to put a 4050 thru the ringer taking up to 8v soon
I will know then where the buck stops I have enough of them to play around with..
As a hobby to me I do not have a stop @ this spec button and because awesome company sends samples. 

Other OT:
In school we found a circuit breaker that was in a flood, 100 amp main it was arching when it should have tripped in the train station, it  took 5k amps and still did not trip, it didn't even start melting,  it was awesome playing around with limits on our installations after that .. Our lives depend on knowing these things as we work hot and loaded most always.  Needless to say we got sweet OT(dbl time) for changing out those now recalled breakers that we discovered..  It was in the newspaper, we felt like superhero's.  Us noobs finding a huge worldwide fault and I was on the crew that removed the initial bad breaker in the station so I felt even more superheroey.. We tested quite a few new breakers and yes many handled 1k amps.  That kind of overrating is horrible lol

My journeyman could have been killed but  he felt weirded out and tested the receded dirty water and it was hot  he never tested the water before that.  So happy I didn't go in the hole first...   He knew it was to warm in the crawl space and checked..     Our usual station down, get out linewagon, reset breaker, carry on, he never got out the truck for that call either, was a helpers job lol..
Just so happens we were chatting about womenz and the convo kept going and the ticket agent was purdy so he wanted to be the big shot lol. 
One of the most dangerous jobs on Earth.  stop ramblings here:::.

[Iamthebadass]

do they even make 1k Ohm thumbwheel trimmers?

[Iamthebadass]

disregard, Yes they do.

[CraigHB]

Its funny at Ti depending on who you talk to, what info you can gather.

I spoke to the guy who built the 08100 chip he was livid about it being used in e cigs as he said, "if you adjust voltages in less than 3 millisecs while the unit is powered it will eventually possibly dramatically fail."  In our use, we usually do not change volts when under power so that is not a huge concern unless using a digital pot.   Then I spoke to another engineer who told me that the 4050c is underrated by a huge margin how big that margin is he didnt exactly say but he did infer it has been tested up to 10A.  Thats an absolutely enormous jump from stated max limit of  2.4amps.  It must be its efficiency is so far in the crapper at higher amps and/or becomes unstable.

TI does tend to underrate their parts so I believe it.  If you're going to overdrive something, they're one of the makers that allow margins wide enough for it.  But yeah, that far out of spec, the part probably fails to meet their high standards so the ratings only cover the range that meets them.

As far as converters blowing due to voltage changes under power, I haven't had that happen.  It's not something you normally do when using an e-cig, but in testing, I'll often ramp the voltage up and down under power and no problems.  Though I'm only using the TI controllers not the whole modules. 

Voltage transients can occur under certain conditions that fry parts.  I've had other controllers blow up from transients so that can be an issue, but not when varying voltage, only on startup.  For a booster, any loss in connectivity to the pot long enough for the converter to react, (only a fraction of a milli-second), can cause the converter to go maximal duty cycle which generates a really high voltage output.  That can happen with a mechanical pot since contact relies on a physical connection, but it wouldn't be a problem for a digital pot.

[Visus]

Analog PoT:
When he told me that I immediately thought hmn not gonna happen with an analog pot lol but yeah analog trimmers,  it does jump up really quickly -- got some strikeout to do in my post there..

I like Ti and for some future products I might need them 4 unrelated to e cigs, I decimal and pro-activate things,  you would be surprised at what these things protract at.   

Global causation at central command 

[CraigHB]

Pots and trimmers are pretty much the same thing electrically.  The only real difference is the size and that trimmers can be multi-turn, but they're also available in single turn.  Both Pots and trimmers use a wiper that runs across a resistance element.  The connectivity is solid when they're new, but once they get wear on them, they can jump around a lot which means connectivity can be lost for small fractions of a second.  Trimmers are only designed to be adjusted a limited number of times so they wear out faster.  Digital pots are made up of an array of solid state resistors so they don't wear out or lose connectivity in any manner.

Wear on the pot is a potential issue for a booster, but I have yet to hear of someone actually blowing a regulator that way.  It's only an issue for a booster.  When a buck regulator loses connectivity on feedback, it also goes to maximal duty cycle, but in that case, it's only input voltage.  If you look at the math, output voltage for a buck converter is duty cycle times input voltage.  For a booster it's 1/(1-D) times input voltage.  Plugging in a large value for duty cycle you can see output approaches input voltage for a buck converter, but goes to a large value for a booster.

[mamu]

Did you get the Murata sample from your OP, breaktru? 

With the Raptor oos, been thinking of tinkering with it.

[Breaktru]

No mamu, never got them.

[mamu]

I think I'll order a few and and play with a new toy. 

[Breaktru]

Go for it.
Have fun

[poorboy]

Hi sensei breaktru. It's been a while since I posted here hope you still remember me. it's also been a long time since I've hold my soldering iron LOL! Is this worth For me to get back to modding? I think it is... Also please PM me your Facebook email so I can invite you to our Small Filipino modding Facebook page that I created a couple of years ago.

[Breaktru]

Hi sensei breaktru. It's been a while since I posted here hope you still remember me. it's also been a long time since I've hold my soldering iron LOL! Is this worth For me to get back to modding? I think it is... Also please PM me your Facebook email so I can invite you to our Small Filipino modding Facebook page that I created a couple of years ago.

Hi poorboy, yes I remember you. Glad you found your way back to the forum 

[poorboy]

Hi poorboy, yes I remember you. Glad you found your way back to the forum 

It feels good to be back! This where I got my masters degree in modding LOL! Have you already played with this new module? BTW I'm still waiting for your Facebook email bro