Fenix LxD/P2D boost driver revealed. 7/16: more (good) pictures of inside the driver.

[wakibaki]

Re: Fenix LxD/P2D boost driver revealed. More pics inside!! Theories of operation wan

If I was setting out to build one of these, I'd be thinking LM2735 SEPIC reg, maybe with an external pass FET, and a 6-pin Microchip PIC.

I'd be trying to stay away from those big black SMT electrolytic caps (looks like they got a few in there).

Ugly little SOB isn't it. Great gobs of solder. Tch, tch!

Has anybody tried to get a circuit diagram and description from Fenix? It's a pretty trivial little design really, not much of an industrial secret. There's a 500mA example circuit in the 2735 datasheet...

w

 

[wintermute]

Re: Fenix LxD/P2D boost driver revealed. More pics inside!! Theories of operation wan

Nice job and nice pics Wintermute :twothumbs

Do you plan to dump the contents of the microcontroller?

Could that actually be accomplished??

 

[zipplet]

Re: Fenix LxD/P2D boost driver revealed. More pics inside!! Theories of operation wan

Microchip offer several versions of their microcontrollers:

Preprogrammed: Not dumpable. Basically you place a large quantity order and microchip ship them preprogrammed and not rewriteable.
One time programmable: Not dumpable usually but I think there is a trick to do it.
Reflashable: If Fenix have any sense they would have enabled the lock/reprogram protection, which stops you being able to reprogram the chip or read out the contents. However, there are probably tricks around it.

(This is assuming fenix use microchip branded microcontrollers)

 

[wintermute]

Re: Fenix LxD/P2D boost driver revealed. More pics inside!! Theories of operation wan

Microchip offer several versions of their microcontrollers:

Preprogrammed: Not dumpable. Basically you place a large quantity order and microchip ship them preprogrammed and not rewriteable.
One time programmable: Not dumpable usually but I think there is a trick to do it.
Reflashable: If Fenix have any sense they would have enabled the lock/reprogram protection, which stops you being able to reprogram the chip or read out the contents. However, there are probably tricks around it.

(This is assuming fenix use microchip branded microcontrollers)

How would we be able to tell if the chip is dumpable? scratch that black goo off and see what the chip is labeled??

If we could bump the chip and figure out the programming, it would be sweet to fix the flash before low and then move the Strobe to the lower levels "Low, Med, High, SOS, Strobe" and leave "Turbo" by itself, so I we can use true momentary tactical switches. :naughty:

 

[zipplet]

Re: Fenix LxD/P2D boost driver revealed. More pics inside!! Theories of operation wan

I agree, it would be sweet. We should start by identifying the chips before trying to work out if they are reflashable. And yes the part number is a big help here, that atleast will tell us if it's preprogrammed, OTP or reflashable.

I'd love to have a Fenix with the flash before low fixed, and a lower low!

 

[BB]

May want to think about how far you take the Public reverse engineering of the Fenix light...

The US Digital Millennium Copyright act (or what ever it is called) does have sections that deals with dumping of code and reverse engineering (I personally don't agree with this law).

And there is just the other issue of using CPF to reverse engineer, compile and distribute "trade secrets"...

Not that this is against the law--or even really unethical--but it can damage the commercial property of a vendor that has been very friendly to CPF.

I don't know the answers--but does make me a bit concerned.

-Bill

 

[wintermute]

May want to think about how far you take the Public reverse engineering of the Fenix light...

The US Digital Millennium Copyright act (or what ever it is called) does have sections that deals with dumping of code and reverse engineering (I personally don't agree with this law).

And there is just the other issue of using CPF to reverse engineer, compile and distribute "trade secrets"...

Not that this is against the law--or even really unethical--but it can damage the commercial property of a vendor that has been very friendly to CPF.

I don't know the answers--but does make me a bit concerned.

-Bill

I really could give a crap less about the US Digital Millennium Copyright act (or what ever it is called) - I also think there are parts which are a major infringement on my personal rights. That being said, out of respect for Fenix R&D and preserving their head start above many other manufacturers, I will not reveal any more information about the operation of the circuit. I still plan to test efficiency numbers with a variety of types of battery configuration (i.e. 1xAA, 2xAA, 1xCR123) at all of the different levels. Stay tuned.

Beyond that if I should happen to have a Fenix with a tactical switch that works, you can imagine how that might happen. :shrug: Also going to look for that software glitch which makes the light flash before the low setting. I have ideas to preserve all of the functions of the light while still having a forward-clicky tail which has a usable momentary switch - we can call it the P2D CTE...Cree Tactical Edition! :twothumbs

 

[BB]

I understand that you might not care about the DMC act--but since this is a US hosted board--the people here have to care to keep out of trouble.

Posting pictures, about how efficient the circuit is (and if it is buck/boost, etc.), what voltages it can safely operate with, how to break it down/modify and stuff into another host--no issue at all (for me).

Internet reverse engineering is something that all manufacturers have to worry about today--And it is not like every other "flashlight" company with $60 has not ordered one and is taking the light apart and reverse engineering as we type...

-Bill

 

[yennit]

Some extra photos beneath the board.

 

[koala]

hi Yennit did you break the inductor? The thing with the coil.

 

[yennit]

Ya, actually the inductor was fried after i mistakenly put the P2D head in the P3D body (with 2 x 16340):mecry:

 

[wintermute]

Ya, actually the inductor was fried after i mistakenly put the P2D head in the P3D body (with 2 x 16340):mecry:

oops

Well, at least you didn't have to worry about damaging the board when you got it out. Thanks for the pics. :thumbsup:

 

[wintermute]

Need some more love with this project. I have included a link in my sig line which points to a thread where I am trying to buy broken or otherwise flaky lights. If anyone out there wants to help make the Fenix CTE (Cree Tactical Edition) - please think about selling (or even donating) your broken or otherwise flaky light.

On another note - should we call it:

The Fenix CTE (Cree Tactical Edition) ---or---
The Fenix TCE (Tactical Cree Edition) ---??---

Thanks for all of the interest so far - after I move I hope to get my new forward clicky switch together.

All the best. :wave:

 

[ace0001a]

Yup nice work on pulling the Fenix electronics...but I think it's funny how there's even a concern about "intellectual property" or copying somebody else's work. Have we forgotten where this light comes from?? I'm not trying to stereotype or anything, but lets face the fact the any product that comes from China is most likely copied from something else. I'm Chinese myself, so I think I know what I'm talking about here. Not that I care because I'm also cheap and I enjoy buying gadgets from China and I'm glad there's dealers like DX and KD to service us. Also, I'm not trying to take away any credit away from the fenix engineers as I'm sure they've tweaked and/or worked on circuit designs that may or may not have come from somebody else. Either way, I just think it's silly to have concern for a product that most likely has had something of it copied from somebody else...my two cents about that anyway...

Flashlight On!! :rock:

 

[RV7]

Yup nice work on pulling the Fenix electronics...but I think it's funny how there's even a concern about "intellectual property" or copying somebody else's work. Have we forgotten where this light comes from?? I'm not trying to stereotype or anything, but lets face the fact the any product that comes from China is most likely copied from something else. I'm Chinese myself, so I think I know what I'm talking about here. Not that I care because I'm also cheap and I enjoy buying gadgets from China and I'm glad there's dealers like DX and KD to service us. Also, I'm not trying to take away any credit away from the fenix engineers as I'm sure they've tweaked and/or worked on circuit designs that may or may not have come from somebody else. Either way, I just think it's silly to have concern for a product that most likely has had something of it copied from somebody else...my two cents about that anyway...

Flashlight On!! :rock:

Are you really Chinese? Do you really know what you're talking about?

 

[RV7]

Great job and great pics... way to go wintermute! Looking forward to receiving the board!

 

[koala]

ace0001a

The idea of boost driver is nothing new, it is in fact one of the fundamentals in power supply electronics. To build a boost driver is easy. You need a boost chip for oscillation, inductor, some caps, transistor or mosfet as the switch, some resistors.

To build a highly efficient boost circuit that owns many competition is hard. As a Chinese, you born to know that there is always a budget when it comes to cost. This makes it even difficult. The Fenix engineers has done a terrific job at designing an efficient circuit and sourcing the right components. I believe the components that is used in Fenix lights are not high end components rather they are the common components available and made locally.

If you read Chinese, may I redirect you to the chinese flashlight forum where the very first Fenix took place. You may have to search 1-2 years back, where the details of Fenix was discussed throughly.

If you can't read Chinese(use a translator), let me remind you. Those Fenix look a like in the market that you are seeing today, is a copy of Fenix. Without Fenix, you probably won't see such an elegant and slim AA light. I remember Fenix AA clicky was the first light to have the form factor and dimension of all the fauxFenix AA you see today. That includes JetBeam AA, Kai REX and all the look a likes. Fenix AA was the original design.

Having said that, it doesn't mean that copying is bad. Albert Einstein once said "The secret to creativity is knowing how to hide your sources.". Manufacturers like JetBeam quickly learned that making a copy isn't good enough. So they came up with tough natural HAIII, supply multiple colored tailcaps, and even multi-level microprocessor controlled. And guess what, Fenix has their digital line now. So who's fake who's real now?!!!! Let's leave this to the designers, it is not up to us to say which is fake. The Chinese, they are doing a counter R&D, a great leap for them from mass manufacturing. It's really actually an evolution. A good time for all of us at CPF.

 

[wintermute]

If you read Chinese, may I redirect you to the chinese flashlight forum where the very first Fenix took place. You may have to search 1-2 years back, where the details of Fenix was discussed throughly.

Man - I have always wished I could read Chinese, but never more then now. They are quite active on that board - Using Google's translator to try to read some things, they seem as active as CPF. I would love to search on there for the original ideas about the Fenix light's coming into being. Wouldn't have to search back more then 1 year to get information about the new LxD/PxD models though - they are all relatively recent. I wonder if they get into the electronics of the board and such. I need some more circuit boards to work with - where are all of those broken/flaky Fenix lights that need new heads?? I need some specimens to work with. :naughty:

 

[koala]

Hi wintermute,

As far as I know, the Fenix designers know their lights would be copied so what they did was to sand the markin off the boost chip in the very early L1P. I have the StainlessSteel AA I haven't open it to check it. The Fenix revolution came after the release of L1P. The designers/manufacturer become tight lipped and post little details in the chinese forums. Sorry, I didn't follow the forum very closely as CPF is busy enough to keep track of.

Vince.

Man - I have always wished I could read Chinese, but never more then now. They are quite active on that board - Using Google's translator to try to read some things, they seem as active as CPF. I would love to search on there for the original ideas about the Fenix light's coming into being. Wouldn't have to search back more then 1 year to get information about the new LxD/PxD models though - they are all relatively recent. I wonder if they get into the electronics of the board and such. I need some more circuit boards to work with - where are all of those broken/flaky Fenix lights that need new heads?? I need some specimens to work with. :naughty:

 

[ace0001a]

Whatever dude, I'm not going to get into a bash fest with you. If you want to be snide about it, that's your thing. I was simply making a point. Yes I am Chinese, born and raised in the good old USA (and yes I realize Americans aren't too popular right now). I see you're Canadian, so I know as I never hear the end of it about our politics from my Canadian cousins in Calgary. And as I was saying in my previous post, I just think it's funny to be concerned about copying of a product from a country where everything is open season for copying.

Are you really Chinese? Do you really know what you're talking about?