FW3A, a TLF/BLF EDC flashlight - SST-20 available, coupon codes public

13647 posts / 0 new
Last post
WalkIntoTheLight
Offline
Last seen: 13 hours 5 min ago
Joined: 12/05/2015 - 10:26
Posts: 2157
Location: Canada

Tom Tom wrote:

I don’t think TK is using anything like PID, that would be just stupid in a dynamic thing like this that doesn’t work like classroom theory.

It’s not an easy thing to control, and the hardware is fixed, this has to be delivered sooner rather than later, otherwise why even bother ?

Pragmatic solutions are required, whilst we know-it-alls chatter amongst ourselves.

How does Zebralight implement their thermal PID control? Because, it’s very response, doesn’t overshoot, and will quickly react both up and down to keep the light at the set thermal level. Granted, the brightest Zebralight is 2300 lumens, so not quite as bright as this light, but it’s still pretty powerful and needs to ramp down in a minute or so. It gets hot, but not too hot to hold.

Tom Tom
Offline
Last seen: 1 year 8 months ago
Joined: 09/10/2017 - 08:30
Posts: 1162

WalkIntoTheLight wrote:
Tom Tom wrote:

I don’t think TK is using anything like PID, that would be just stupid in a dynamic thing like this that doesn’t work like classroom theory.

It’s not an easy thing to control, and the hardware is fixed, this has to be delivered sooner rather than later, otherwise why even bother ?

Pragmatic solutions are required, whilst we know-it-alls chatter amongst ourselves.

How does Zebralight implement their thermal PID control? Because, it’s very response, doesn’t overshoot, and will quickly react both up and down to keep the light at the set thermal level. Granted, the brightest Zebralight is 2300 lumens, so not quite as bright as this light, but it’s still pretty powerful and needs to ramp down in a minute or so. It gets hot, but not too hot to hold.

My reference to “classroom theory” is because in this torch the temperature sensor is not closely coupled to the parts that are trying to be controlled. So it is a lot more difficult to do, and I am impressed by how well it works.

I regard what TK is doing as a pragmatic approach, using empirical methods, rather than a theoretical analysis.

Control engineering is quite a deep subject, I only studied it just enough to realise how little I understood.

See e.g.

https://en.wikipedia.org/wiki/PID_controller

https://en.wikipedia.org/wiki/PID_controller#Limitations_of_PID_control

to get an idea of some of the complexity.

No idea about Zebralights, but clearly they are doing something right. ISTR from posts here that DrJones has developed some impressive temperature control as well, but can’t find the details.

Edit: found DrJones’ work: http://budgetlightforum.com/node/43140

Tom Tom
Offline
Last seen: 1 year 8 months ago
Joined: 09/10/2017 - 08:30
Posts: 1162

PS: here is some less highbrow explanation, from the great Robert A. Pease, Applications Engineer for Nat. Semi back in the day, I’ve probably read every application note he ever wrote, required reading for any analogue engineer.

http://www.electronicdesign.com/analog/whats-all-p-i-d-stuff-anyhow

manithree
Offline
Last seen: 9 hours 36 min ago
Joined: 01/12/2013 - 01:08
Posts: 487
Location: Orem, UT, USA
Tom Tom wrote:
PS: here is some less highbrow explanation, from the great Robert A. Pease

Oh man, that brings back memories. I used to subscribe to EDN just for Pease Porridge.

sbslider
sbslider's picture
Offline
Last seen: 3 hours 52 min ago
Joined: 01/22/2017 - 13:41
Posts: 1637
Location: United States

manithree wrote:

Oh man, that brings back memories. I used to subscribe to ED just for Pease Porridge.
Thumbs Up

PocketSammich wrote: I don’t need this, but I want it. Please sign me up.

Tom Tom
Offline
Last seen: 1 year 8 months ago
Joined: 09/10/2017 - 08:30
Posts: 1162

manithree wrote:

Oh man, that brings back memories. I used to subscribe to ED just for Pease Porridge.

It was called EDN back then (Electronic Design News) and no I didn’t have to subscribe, in fact dealing with the semiconductor reps. and their latest stuff, and future plans, could have taken up all my time and got in the way of the job. But things were evolving so fast.

Evaluation samples were plied upon us, and meetings often took place down the pub (or posh restaurant) at lunchtime or after work, happy days.

And we all knew each other.

Stereodude
Offline
Last seen: 1 year 2 days ago
Joined: 03/16/2013 - 21:14
Posts: 521
Location: US of A

Tom Tom wrote:
PS: some more detail on how to use the LED Vf as it’s own temperature sensor:

http://www.electronicdesign.com/lighting/use-forward-voltage-drop-measur...

PPS: You already have a constant current source on the driver (x1 7135) so if you could arrange a second set of wires to the LED (4 wire probe) feeding an ADC input to the MCU, you could do it, with just the tiniest flicker when taking the measurement. Guessing at 2mV/degreeC slope, you’d be looking to resolve say 200 mV over the range 0-100C, on the say 3V Vf, which sounds do-able.

This would have to be a high precision differential measurement synchronized to the PWM cycle in order to get useful data.
Tom Tom
Offline
Last seen: 1 year 8 months ago
Joined: 09/10/2017 - 08:30
Posts: 1162

Stereodude wrote:
Tom Tom wrote:
PS: some more detail on how to use the LED Vf as it’s own temperature sensor:

http://www.electronicdesign.com/lighting/use-forward-voltage-drop-measur...

PPS: You already have a constant current source on the driver (x1 7135) so if you could arrange a second set of wires to the LED (4 wire probe) feeding an ADC input to the MCU, you could do it, with just the tiniest flicker when taking the measurement. Guessing at 2mV/degreeC slope, you’d be looking to resolve say 200 mV over the range 0-100C, on the say 3V Vf, which sounds do-able.

This would have to be a high precision differential measurement synchronized to the PWM cycle in order to get useful data.

You don’t need a diff-amp if you can sample both signals fast enough. But I’d suggest just clamping one to +V and sampling the switched signal, gets rid of the offset once you subtract cell voltage. It might be good enough. Of course sampled in-between regular operation, that’s why I suggested it could be done in a blink, in-between normal operation.

Just a mad idea though.

Edit: If this is doing without the voltage divider to measure Vbatt, as I suspect, then it could be a bit approximate, but measured Vbatt vs. LED Vf should still track if they are coming through the same pin to the same ADC.

One way to make that happen, put a large pullup fromVbatt onto the ADC pin. Measure Vbatt with everything else turned off (7135 and FET). Then pulse the LED with one 7135 for a few milliseconds, if necessary turning up the gain, measure, subtract, calculate, job done. All through one pin (possibly multiplexed with something else).

For best precision, take a slightly different two measurements, not Vbatt open circuit but Vbatt whilst driving the pulse (two pulses required)..

Grappler
Offline
Last seen: 8 months 2 days ago
Joined: 02/28/2018 - 21:22
Posts: 89

I’m fairly new around here and have learned a lot from BLF. I’ve since picked up a BLF A6, an Astrolux C8 (thanks to WalkIntoTheLight’s review crushing the Convoy C8) and a Massdrop/Lumintop Brass Tool AAA.

As for PWM, I’ve heard it’s used in some cheap or budget lights as a way of cutting costs. I don’t know much about it. But I do find it annoying on an older light I have.

Would someone please clarify:

a.) why the FW3A will use PWM and

b.) if/how its use of PWM will have minimal noticeable effect?

Thank you!

 

 

ToyKeeper
ToyKeeper's picture
Offline
Last seen: 17 hours 24 min ago
Joined: 01/12/2013 - 14:40
Posts: 10623
Location: (469219) 2016 HO3
Grappler wrote:
I’ve since picked up a BLF A6, … As for PWM, I’ve heard it’s used in some cheap or budget lights as a way of cutting costs. I don’t know much about it. But I do find it annoying on an older light I have.

But you don’t find PWM annoying on the BLF-A6?

If you don’t mind PWM on the A6, you won’t mind it on the FW3A. They both use the same method, except the FW3A does it better. What people dislike is slow PWM, and that’s not what the FW3A does.

It’s about more than cost. A full current regulation circuit also requires more space and fancier heat sinking, and introduces a variety of other complications depending on how it’s done.

Grappler
Offline
Last seen: 8 months 2 days ago
Joined: 02/28/2018 - 21:22
Posts: 89

ToyKeeper wrote:
But you don’t find PWM annoying on the BLF-A6?

If you don’t mind PWM on the A6, you won’t mind it on the FW3A. They both use the same method, except the FW3A does it better. What people dislike is slow PWM, and that’s not what the FW3A does.

It’s about more than cost. A full current regulation circuit also requires more space and fancier heat sinking, and introduces a variety of other complications depending on how it’s done.

Thanks for clarifying. You’re right… It’s the slow PWM I don’t like. I don’t notice it on the A6 and am pleased it will be even better on the FW3A.

 

 

WalkIntoTheLight
Offline
Last seen: 13 hours 5 min ago
Joined: 12/05/2015 - 10:26
Posts: 2157
Location: Canada
Grappler wrote:
Thanks for clarifying. You’re right… It’s the slow PWM I don’t like. I don’t notice it on the A6 and am pleased it will be even better on the FW3A.

Most manufacturers now seem to be doing PWM the right way: fast. I still prefer current regulation, but you generally only get that on more expensive lights. I don’t find fast PWM annoying at all, it’s more for reasons of efficiency and well-regulated output that I prefer current regulation. For budget lights, it seems that a FET driver and PWM is the way they’re all done (for the high modes).

I think the FW3A shows more promise by using 8 (or is it 10?) 7135 chips. That should get much better regulated output on higher modes. Though, I still find the Convoys that use 8×7135 chips still suffer from dropping output as the battery voltage drops, well before I would have thought the voltage should start having an effect. It’s not as bad as pure FET, though.

Tom Tom
Offline
Last seen: 1 year 8 months ago
Joined: 09/10/2017 - 08:30
Posts: 1162
WalkIntoTheLight wrote:
I still find the Convoys that use 8×7135 chips still suffer from dropping output as the battery voltage drops, well before I would have thought the voltage should start having an effect. It’s not as bad as pure FET, though.

What else can you expect, when driving a typical white LED from a LiIon cell with a crude driver ?

The voltage mis-match is great. Huge inefficiency when the cell is full, and it barely works as the cell discharges below e.g. 3V (lots of energy still left there by the way)

The efficiency is all over the place (7135 and anything linear obviously better, until they drop out), the FETs run open-loop on crude PWM at the worst efficiency, with no voltage compensation AFAIK.

There are far better ways of doing this, but they cost a tiny bit more, and take skill to design.

Boost, Buck, Buck-Boost. Choose a good one and you might double your cell life compared with a crude driver. Makes all the debate about “what is the best cell” a bit moot.

It is long past the time when 7135/FET drivers should have any credibility, no-matter how easy they are to design and cheap to manufacture.

Passim.

ToyKeeper
ToyKeeper's picture
Offline
Last seen: 17 hours 24 min ago
Joined: 01/12/2013 - 14:40
Posts: 10623
Location: (469219) 2016 HO3

JaredM wrote:
is it possible to at least get a placeholder solder pads on the MCPCB?

Could you explain the tube/retaining ring issue in more detail? I’d love to help …

It won’t be feasible to change the MCPCB design again before production.

The inner tube issue is already solved, I think, but we’re waiting on test results to be sure.

WalkIntoTheLight wrote:
How does Zebralight implement their thermal PID control?

Voodoo.

And probably more classroom theory than I’m using. When it oscillates, the oscillations are very regular, suggesting that it probably has a more formal design than what I’m using, or at least a much better signal-to-noise ratio on the sensor data. And probably more “I” with less “D”.

What I’m doing is a form of PID, but it’s less of a proper academic “Hogwarts/Brakebills” PID and more of a hedge witch “street” PID.

Tom Tom wrote:
ISTR from posts here that DrJones has developed some impressive temperature control as well, but can’t find the details.

I have a H17F in a solid copper host with some serious thermal mass, and did some testing on its thermal response. This plot shows the H17F and an early version of Anduril from ~10 months ago. I found that DrJones’ method appeared to drop 1 PWM level every 0.5 seconds or so, until the FET was no longer active, then drop 1 PWM level every 2 seconds or so on the 7×7135 channel, until it was no longer overheating. It took about 8 minutes to stabilize, because the adjustment was very slow. Very smooth though, and it seemed okay in such a solid host. Bumps on its graph were where I accidentally moved the light while checking its surface temperature.

Meanwhile, Anduril stabilized in about a minute. These results are not directly comparable though, due to being in different hosts with different power levels. So at some point I should probably compare them in the same host to find out if the H17F can speed up when necessary.

Tom Tom wrote:
how to use the LED Vf as it’s own temperature sensor…

On the FW3A, there was a spare pin so it actually has an “optic nerve” built in to be able to use the LED as a light sensor. But the way it’s designed probably wouldn’t work for temperature for a variety of reasons. Mostly, the reading is designed to auto-center on zero over time, so edges are visible but absolute levels are not.

The first prototype will likely soon become a dev host for optical sensor features. Those aren’t planned for release, but perhaps in a later version. Configuring a flashlight from a computer screen is a neat trick, but it’s mostly not very practical so I haven’t prioritized it.

ToyKeeper
ToyKeeper's picture
Offline
Last seen: 17 hours 24 min ago
Joined: 01/12/2013 - 14:40
Posts: 10623
Location: (469219) 2016 HO3
Tom Tom wrote:
It is long past the time when 7135/FET drivers should have any credibility

People sometimes complain about linear drivers, but for the most part they work fine as long as the emitters match the power source. The main benefit of a buck/boost is being able to run mismatched voltages, like XHP35 on a single cell.

Drivers could certainly be optimized more, but it seems like a matter of diminishing returns. Fancier drivers provide benefits most people won’t really notice, and sometimes the extra complexity comes with significant baggage. Sometimes it’s worth the trouble, sometimes not.

iamlucky13
Online
Last seen: 5 min 27 sec ago
Joined: 06/22/2018 - 09:18
Posts: 882
Location: USA
WalkIntoTheLight wrote:
Though, I still find the Convoys that use 8×7135 chips still suffer from dropping output as the battery voltage drops, well before I would have thought the voltage should start having an effect. It’s not as bad as pure FET, though.

On high or lower modes? The Convoy and similar drivers have an odd quirk that causes poor regulation on lower modes.

I built my first Convoy recently using an 8×7135 Qlite driver – pretty similar to the Convoy driver, but I have STAR firmware on mine. Out of curiosity, I tested the regulation with a linear power supply. Mine held regulation at ~3 Amps until the input level dropped below 3.4V when driving a 2.8-2.9V rated 219C. It dropped to 50% of initial current draw at 3.15V.

Considering Nichia’s datasheet shows the forward voltage is 3.4V at roughly that current level, this $5 driver seemed to have perfect regulation. There are caveats for voltage binning and the temperature dependence of Vf, but they don’t change the conclusion much.

Surprisingly, regulation was far worse on lower modes.

My 750 mA target (25%) mode fell out of regulation at 3.9V.
My 90 mA target (3%) mode was already out of regulation at 4.3V.

This wasn’t actually a surprise to me. I was looking for it specifically because when shopping for a driver, I noticed HKJ documented it over 4 years ago. He speculated based on oscilloscope data that the 7135 chips respond too slowly to the 16 kHz PWM to turn on fully when the duty cycle is low. Maukka measured similar when he did a more cursory output test of an S2+.

However, the D4 also uses a high frequency PWM for its 7135 chip, yet does not share this issue. I don’t know if it is due to the specific brand of 7135 used, a driver design issue, or if Toykeeper, TomE or others know a firmware trick to avoid it.

Roc32
Offline
Last seen: 2 years 3 months ago
Joined: 06/21/2018 - 11:15
Posts: 5

Please add me to the list (2)

ToyKeeper
ToyKeeper's picture
Offline
Last seen: 17 hours 24 min ago
Joined: 01/12/2013 - 14:40
Posts: 10623
Location: (469219) 2016 HO3

iamlucky13 wrote:
Surprisingly, regulation was far worse on lower modes.

He speculated based on oscilloscope data that the 7135 chips respond too slowly to the 16 kHz PWM to turn on fully when the duty cycle is low.

However, the D4 also uses a high frequency PWM for its 7135 chip, yet does not share this issue. I don’t know if it is due to the specific brand of 7135 used, a driver design issue, or if Toykeeper, TomE or others know a firmware trick to avoid it.

All of the above. The FW3A uses a few methods to avoid that problem:

  • Chip brand: “Raptor claw” 7135 chip chosen specifically for its activation speed, so it will perform well with short pulses. The low-mode problems are mostly seen on “failboat” 7135 chips.
  • Driver design: 1×7135 chip on its own channel, so it uses the 350mA Vf instead of the 3A Vf, and can thus regulate longer.
  • Firmware: Slower PWM frequency at the lowest levels, like moon, to improve stability and reduce voltage sensitivity. Also reduces total power draw significantly, so moon runs about 3X longer than it would at full speed. (the D4 doesn’t do this, but the FW3A does)

So… regulation on this thing actually works pretty well.

iamlucky13
Online
Last seen: 5 min 27 sec ago
Joined: 06/22/2018 - 09:18
Posts: 882
Location: USA

ToyKeeper wrote:
All of the above. The FW3A uses a few methods to avoid that problem:
  • Chip brand: “Raptor claw” 7135 chip chosen specifically for its activation speed, so it will perform well with short pulses. The low-mode problems are mostly seen on “failboat” 7135 chips.
  • Driver design: 1×7135 chip on its own channel, so it uses the 350mA Vf instead of the 3A Vf, and can thus regulate longer.
  • Firmware: Slower PWM frequency at the lowest levels, like moon, to improve stability and reduce voltage sensitivity. Also reduces total power draw significantly, so moon runs about 3X longer than it would at full speed. (the D4 doesn’t do this, but the FW3A does)

So… regulation on this thing actually works pretty well.

Aha! Thanks for the reply. I spent far too much time researching this issue before I gave up trying to find answers and bought parts for my build.

I should have just created an account here earlier to ask, instead of digging through countless old threads.

But I’m glad I mentioned it in this thread, because now I know the concern is already addressed in the FW3A.

Unfortunately, it seems there are a lot of drivers out there using the lower quality chips.

bansuri
Online
Last seen: 2 min 58 sec ago
Joined: 01/30/2017 - 23:43
Posts: 493
Location: Land of Lincoln

All this from a $30-$36 light? Outrageous!
This thread, (well, portions of it) should be required reading for all flashlight manufacturers.

“Waddaya think, Joey? High, medium, low? Or low, medium, high?”
“Howzabout medium, low, high?”
“Brilliant! We’ve got our UI,.. what else?”
“Wuddabout some flashy stuff?”
“Scope creep! We’re done!”
(end scene)

Silentcropduster
Silentcropduster's picture
Offline
Last seen: 11 months 1 day ago
Joined: 10/17/2015 - 23:55
Posts: 56
Location: Ohio

Sign me up for 1, maybe 10 Smile

In the closet flashlightaholic!

My collection: 4000 lumen XHP70 "Jayrod" mag mod, Solarforce L2T with XML2, BLF A6, Nitecore EC4S, + many more!

bansuri
Online
Last seen: 2 min 58 sec ago
Joined: 01/30/2017 - 23:43
Posts: 493
Location: Land of Lincoln

Silentcropduster wrote:
Sign me up for 1, maybe 10 Smile

I know what you mean! I’m leaning that way thinking of a couple extra for my kids.
alifpb98
Offline
Last seen: 11 months 3 days ago
Joined: 09/02/2017 - 10:42
Posts: 56
Location: Bogor, Indonesia

Forfive me if this has been asked before, does FW3A will have PID for thermal control? Thanks Smile

JasonWW
JasonWW's picture
Offline
Last seen: 10 hours 24 min ago
Joined: 10/22/2016 - 11:41
Posts: 12733
Location: Houston Texas

alifpb98 wrote:
Forfive me if this has been asked before, does FW3A will have PID for thermal control? Thanks Smile

ToyKeeper just said this a couple posts above.
ToyKeeper wrote:

What I’m doing is a form of PID, but it’s less of a proper academic “Hogwarts/Brakebills” PID and more of a hedge witch “street” PID.

So yes, it will increase brightness if the light is cooled down. I assume that’s what your are asking.

Texas Ace Lumen Tube and JoshK Sphere calibrated with Maukka lights

Click this to go to signature links. I'm still around, just not reading many new threads.

alifpb98
Offline
Last seen: 11 months 3 days ago
Joined: 09/02/2017 - 10:42
Posts: 56
Location: Bogor, Indonesia

Didn’t realize that post, mostly because i only took a quick glance of most posts here. Facepalm
Anyway thank you.

iamlucky13
Online
Last seen: 5 min 27 sec ago
Joined: 06/22/2018 - 09:18
Posts: 882
Location: USA

Please add me to the list for one (1).

Body color is not very important to me, but I think the silvery color of the prototype looks nice, even if not quite like bare aluminum.

JasonWW
JasonWW's picture
Offline
Last seen: 10 hours 24 min ago
Joined: 10/22/2016 - 11:41
Posts: 12733
Location: Houston Texas

alifpb98 wrote:
Didn’t realize that post, mostly because i only took a quick glance of most posts here. Facepalm
Anyway thank you.

You probably don’t need to read every post, but ToyKeeper is one of the main FW3A team members who actually posts updares on this project. It’s always good to read her posts, even if the techno stuff goes over your head. Lol

FW3A Team
Fritz15: Design
Tommy TLF: General TLF communication
DEL: Driver
Tom E: Firmware (originally), driver
ToyKeeper: Firmware / UI, BLF gardening
The Miller: General BLF communication
pepinfaxera: Interest list management
MRsDNF: Early prototyping
Neal: Facilitating tasks in China
Lumintop: Manufacturing

Texas Ace Lumen Tube and JoshK Sphere calibrated with Maukka lights

Click this to go to signature links. I'm still around, just not reading many new threads.

rizaoztop
Offline
Last seen: 5 months 4 weeks ago
Joined: 06/02/2011 - 07:54
Posts: 174
Location: Turkey

Who will be seller ? I am asking because i have payment issues with GB.

pepinfaxera
Offline
Last seen: 23 hours 14 min ago
Joined: 06/25/2015 - 12:53
Posts: 305
Location: Gijón - Spain - Europe

Updated list : … . . . . C L O S E D
.
Primary Interest List, (main): See Post # 4, Page 1 .
.
.
.
pepinfaxera: Interest List: See #Post , Page 111

pepinfaxera: Interest List, duplicate: See # Post , Page 71 ,
.
-
1233 – # Post . bansuri
.
New requests:
.
Correcting: …
.
1125 – # Post . Bob_McBob

Bob_McBob wrote:
I’m 1038, could you put me down for another two please?
See # Post: 2856, page 96
Apologies, I’m sorry.
I need to edit list.
Greetings.
- .
- .
-18 Off : # Post . DB Custom , See # Post . … “Delete, Remove”
.
-1174 Off : # Post . CM2010 , See #Post . … “Delete, Remove”
.
-931 Off : # Post . darrylo 3nd … “Delete, Remove”
-932 Off: # Post . darrylo 4nd … “Delete, Remove”
.
-1344 Off : See # Post Coscar, delete , “Remove”
- .
- .
1234 – # Post . mniezen
1235 – # Post . mniezen
1236 – # Post . FBsLights
1237 – # Post . preface
1238 – # Post . whopist
1239 – # Post . jaynick
1240 – # Post . jaynick
1241 – # Post . jaynick
1242 – # Post . tjl014
1243 – # Post . tjl014
1244 – # Post . Cutchya
1245 – # Post . I LIKE FLASHLIGHTS
1246 – # Post . DoubleU
1247 – # Post . ActiveAl
1248 – # Post . severide
1249 – # Post . Tarvos
1250 – # Post . Tarvos
1251 – # Post . kmwc72 CN
1252 – # Post . kmwc72 CN
1253 – # Post . ActiveAl
1254 – # Post . Lion42
1255 – # Post . Lion42
1256 – # Post . andyxxx
1257 – # Post . andyxxx
1258 – # Post . flashycali
1259 – # Post . Aussie78
1260 – # Post . dmsoule
1261 – # Post . dmsoule
1262 – # Post . manithree
1263 – # Post . tvizk
1264 – # Post . raqin
1265 – # Post . retsyx
1266 – # Post . Bervilat
1267 – # Post . kubed_zero
1268 – # Post . kubed_zero
1269 – # Post . korylprince
1270 – # Post . Ratus
1271 – # Post . Edindevon
1272 – # Post . GalaxyWide
1273 – # Post . Medicijnman
1274 – # Post . Nash_Vegas
1275 – # Post . Moomoomao
1276 – # Post . Moomoomao
1277 – # Post . Brinkmann
1278 – # Post . Brinkmann
1279 – # Post . bonfire
1280 – # Post . Moparguy
1281 – # Post . Moparguy
1282 – # Post . .-’_
………….. – 1282 See: .-’_
1283 – # Post . Nooner
1284 – # Post . Atom00
1285 – # Post . javipiloto
1286 – # Post . Lfatman
1287 – # Post . DarkParagon
1288 – # Post . Crazy999
1289 – # Post . LanternGuy
1290 – # Post . samnavy
1291 – # Post . Random Dan
1292 – # Post . finnegans
1293 – # Post . TheSoulless78
1294 – # Post . wiley07
1295 – # Post . jinjin19
1296 – # Post . QwertzHz
1297 – # Post . Cyzan
1298 – # Post . Cyzan
1299 – # Post . cujo255
1300 – # Post . geetee03
1301 – # Post . apurva
1302 – # Post . apurva
1303 – # Post . Marubae
1304 – # Post . HONDARIDER
1305 – # Post . HONDARIDER
1306 – # Post . yokomus
1307 – # Post . Chatika vas Paus
1308 – # Post . Chatika vas Paus
1309 – # Post . Snoballz
1310 – # Post . spaceminions
1311 – # Post . Mr.Scott
1312 – # Post . lohtse
1313 – # Post . lohtse
1314 – # Post . brettr1
1315 – # Post . gkushev
1316 – # Post . gkushev
1317 – # Post . wiley07
1318 – # Post . wiley07
1319 – # Post . Yoav.Klein
1320 – # Post . Bd7
1321 – # Post . alejo
1322 – # Post . hiker89
1323 – # Post . hiker89
1324 – # Post . hiker89
1325 – # Post . NordicMist
1326 – # Post . wheelgunwordslinger
1327 – # Post . Dsvist12
1328 – # Post . Dsvist12
1329 – # Post . Doobyscoo
1330 – # Post . mrgreengenes42
1331 – # Post . misterpearguy
1332 – # Post . MobileEMP
1333 – # Post . MobileEMP
1334 – # Post . MobileEMP
1335 – # Post . rennet
1336 – # Post . lew123
1337 – # Post . zeroflow
1338 – # Post . duhduhduhdiabeetus
1339 – # Post . Nortson
1340 – # Post . Hallamski
1341 – # Post . michaeltmohr
1342 – # Post . Glas4d
1343 – # Post . Glas4d
.
1344 – # Post . Coscar
-1344 – See # Post Coscar, delete
.
1344 – # Post . gemmell
1345 – # Post . gemmell
1346 – # Post . a_idiot
1347 – # Post . jaharkes
1348 – # Post . madness
1349 – # Post . arisdes
1350 – # Post . Zeratull
1351 – # Post . severide
1352 – # Post . TheShadowGuy
1353 – # Post . Cursecut3r
1354 – # Post . Hesh24
1355 – # Post . Tony Cape
1356 – # Post . sbslider
1357 – # Post . LightUpTheDark
1358 – # Post . Jagger
1359 – # Post . soldsoulrockroll
1360 – # Post . ReallyInToCheese
1361 – # Post . noobsanpu
1362 – # Post . BurningPlayd0h
1363 – # Post . headburger
1364 – # Post . Phaze13
1365 – # Post . Iselldrugsforgolf
1366 – # Post . Typevii
1367 – # Post . tkd15
1368 – # Post . xikteny
1369 – # Post . bushmaster
1370 – # Post . kevinw0lf
1371 – # Post . scottie888
1372 – # Post . Gondwanaland
1373 – # Post . cannesahs
1374 – # Post . Polyesterboy
1375 – # Post . the0dore3524
1376 – # Post . Stereodude
1377 – # Post . CitizenK
1378 – # Post . bento_blf
1379 – # Post . klrman
1380 – # Post . yokomus
1381 – # Post . KJ4BXT
1382 – # Post . KJ4BXT
1383 – # Post . ale9g
1384 – # Post . Penguin
1385 – # Post . Penguin
1386 – # Post . waxing twilight
1387 – # Post . Roc32
1388 – # Post . Roc32
1389 – # Post . iamlucky13
1390 – # Post . Mops1
1391 – # Post . Mops1
1392 – # Post . wheremydonky
1393 – # Post . wheremydonky
1394 – # Post . wheremydonky
1395 – # Post . psumo
1396 – # Post . adirus
1397 – # Post . geetee03
1398 – # Post . zotee123
1399 – # Post . anycolourfloyd
1400 – # Post . CabalGrim
1401 – # Post . Lick
1402 – # Post . ttylamg
1403 – # Post . Cereal_killer
1404 – # Post . Jay
1405 – # Post . mb200k
1406 – # Post . stolikat
1407 – # Post . TonyG
1408 – # Post . asciiphil
1409 – # Post . Fady
1410 – # Post . Fady
1411 – # Post . Fady
1412 – # Post . lucydog
1413 – # Post . lightknot
1414 – # Post . lightknot
1415 – # Post . xertian
1416 – # Post . xertian
1417 – # Post . Enlightened1
1418 – # Post . Enlightened1
1419 – # Post . elnino
1420 – # Post . gottawearshades
1421 – # Post . 3061fps
1422 – # Post . andrewmac
1423 – # Post . andrewmac
1424 – # Post . firstcipher
1425 – # Post . skinny_tie
1426 – # Post . Nooner
1427 – # Post . Cereal_killer
1428 – # Post . Cereal_killer
1429 – # Post . bushmaster
1430 – # Post . kollers
1431 – # Post . Geese
1432 – # Post . caplang
1433 – # Post . vadimax
1434 – # Post . MonkeyLight
1435 – # Post . MonkeyLight
1436 – # Post . MonkeyLight
1437 – # Post . MonkeyLight
1438 – # Post . justaguy
1439 – # Post . justaguy
1440 – # Post . HeavyD3
1441 – # Post . HeavyD3
1442 – # Post . knuckles
1443 – # Post . Mops1
1444 – # Post . thejinn
1445 – # Post . fusion_m8
1446 – # Post . justanotherguy
1447 – # Post . Geese
1448 – # Post . JohnnyUtah
1449 – # Post . loki993
1450 – # Post . e1000
1451 – # Post . jamio
1452 – # Post . hodor
1453 – # Post . Ilmatic
1454 – # Post . Ilmatic
1455 – # Post . atasuke_
1456 – # Post . AcIDsNaZz
1457 – # Post . Desert Lumens
1458 – # Post . bulbeee
1459 – # Post . Melven
1460 – # Post . neBstress
1461 – # Post . autoxer
1462 – # Post . RichardBrown
1463 – # Post . Valerianis
1464 – # Post . takumi86
1465 – # Post . Gravedigger1
1466 – # Post . MascaratumB
1467 – # Post . RandyC
1468 – # Post . RandyC
1469 – # Post . coban
1470 – # Post . coban
1471 – # Post . eas
1472 – # Post . Delta_V
1473 –
1474 –
1475 –
1476 –
1477 –
1478 –
1479 –
1480 –
. – - ,
. – - ,
NOTE: If I overlooked a post, PLEASE IM me and i’ll edit for correction.
. -
. -
. . . . . . . . . . C L O S E D

Sorry for my bad English
(google translator) , (https://www.deepl.com/translator)

WalkIntoTheLight
Offline
Last seen: 13 hours 5 min ago
Joined: 12/05/2015 - 10:26
Posts: 2157
Location: Canada

Tom Tom wrote:

The efficiency is all over the place (7135 and anything linear obviously better, until they drop out), the FETs run open-loop on crude PWM at the worst efficiency, with no voltage compensation AFAIK.

There are far better ways of doing this, but they cost a tiny bit more, and take skill to design.

Boost, Buck, Buck-Boost. Choose a good one and you might double your cell life compared with a crude driver. Makes all the debate about “what is the best cell” a bit moot.

Totally agree. This summer, I replaced my BLF A6 cycling light with a Zebralight SC600w MkIV Plus. The BLF A6 uses a FET+1 driver with a XP-L, and the Zebralight a boost driver with an XHP50.2. I like to use about 700 lumens when cycling, and the BLF A6 would give me about 1 hour of output before it dims too much to be useful to me. The Zebralight gives me a constant 700 lumens for almost 3 hours, until the battery is drained to 2.8v. (Both using a Sanyo GA cell.)

While I like the BLF A6 as a casual light, there are some circumstances where FET will not do, and even a 8×7135 like a Convoy won’t do either. When run-time and constant output is required, you gotta go boost or buck/boost.

I wonder if there’s a way in firmware to increase the PWM duty cycle of a FET driver as the battery voltage drops? It wouldn’t help with efficiency, but it would help to regulate output much better (on levels below max).

Pages