koala
Flashlight Enthusiast
I have been working on this project for months, it has been always my dream of such an electronic switch. Perhaps this is the best upgrade to any flashlight that fits a kroll. I am excited, I just wish to share my work/mod/design to you all, it's certainly a hard work for me as I do not have much skill in electronics, I am only a programmer. The Intelligent Kroll has a lot more to improve, the current version unfortunately a poor prototype that has some more to improve on.
Here I present and introduce the Intelligent Kroll.
My apologies for the dim picture. I took it in a hurry. You can see a enamel wire stretching to the below right, it goes to +ve of the battery. I know this is extremely unreliable but it's the only way I can think of. The microcontroller sits under the kroll cap. The mosfet and two resistors on top of the avr. All freeformed, no space for pcb. I am not an ee engineer, the circuit is built to work and I find it stable.
Update: 3 September 2003
Wooohooo! I looked through my stash and from an old cdrom, I got some flexible pcb. It's a PITA to split these properly as the strips are so close together. I believe this is a connection to the brushless motor that spins the cd. This flexible pcb is a very nice solution to the earlier enamel coated wire which is much weaker. I guess it's now safe to route +ve to the uP. Another thing about this flexipcb is that it's pretty much fire proof. At first I wanted to use my soldering gun to melt away the coating but it refuse to even weaken. In the end I had to use the razor to shave away the coating. Perhaps the negative contact spring will have to be removed so there won't be extra play to stress the flexible pcb when assembling or disabling the battery. Ok, I haven't quote the price for making these but I guess it won't be too expensive. I might be able to get this printed for the micro, if I could relocate the micro to another position in the kroll. Then the other parts can also go on to the flexible pcb.
Why Kroll? I spent countless hours looking for alot of alternatives such as nylon nuts and other items that has threads but neither of them have the suitable thread I need. Customizing is out of question. The Kroll cheap and strong as an electronic host. The rubber boots is nice waterproof.
The Intelligent Kroll, is no more mechanical or technically less mechanical that people hate. However the tactile switch is still mechanical. Inside the modified kroll, house an Atmel AtTinyAvr that works all the way down to 1.8volts. During operational testing I find that works down to 1.6volts without any problem. The microcontroller switches a low resistance n-channel mosfet at variable duty(PWM) to archieve dimming. If you know which AVR I am talking about, yes it's the one without SRAM without PWM. So you know it's a pain to program. However, it's cheap and it suck little current with lowest operating voltage.
Features
A few features of the iKroll (in a ARC LSH)
ShortBurst - 10 seconds of 200ma light
FullBurst - Infinite on 200ma light
User Preset - 10ma to 330ma (10 levels, maximum drive depends on the dc2dc circuit)
Blink - blink at 100ma once every 3 second
EDIT: I should add a momentary on at full brightness for tactical use as it is important. I do not expect this switch to be used in mission critical situation as it is still in development stages. Thanks to Otokoyama for pointing out.
A short press will put the light in to ShortBurst another press brings you in to FullBurst and so on. A long press will shutdown the light in whatever mode.
A feature that I like is that the light will slowly dim to shutdown. Another feature is the Xenon burst, the light will flicker then slowly steady to FullBurst. When all stable, I am going to mod my LSH sense resistor so I can have a boost function /ubbthreads/images/graemlins/naughty.gif.
Need Improve
The Intelligent Kroll is quite dumb actually. The switching frequency for Zetex, Linear(ARC LSH) and direct drive are totally different therefore the Kroll need to be programmed specifically. Perhaps I should include three sets of different dimming frequencies into the Kroll so it can be selected when working with different type of circuits. The 2K flash memory is really preventing anymore features getting added. I need more space!
Perhaps I should switch to the new tiny13 that has PWM and it works all the way down to 1.8volts. A better solution is to switch to a totally new platform EM Microelectronic EM6680, looks very good with low 1.2volts operating voltage and PWM. However emmarin seems to be a busy company and never reply my emails and the information to program it might be scare. Perhaps the mcu is too good to be true and never exists or oo expensive for them to give out samples.
Ok this is really off topic but I have to say this /ubbthreads/images/graemlins/twakfl.gif /ubbthreads/images/graemlins/hahaha.gif
I have to thank my girl for being extremely tolerant for the pass few weeks when I work really hard. She is the most loving and yet caring person in the world.
Cheers,
Vince.
Here I present and introduce the Intelligent Kroll.
My apologies for the dim picture. I took it in a hurry. You can see a enamel wire stretching to the below right, it goes to +ve of the battery. I know this is extremely unreliable but it's the only way I can think of. The microcontroller sits under the kroll cap. The mosfet and two resistors on top of the avr. All freeformed, no space for pcb. I am not an ee engineer, the circuit is built to work and I find it stable.
Update: 3 September 2003
Wooohooo! I looked through my stash and from an old cdrom, I got some flexible pcb. It's a PITA to split these properly as the strips are so close together. I believe this is a connection to the brushless motor that spins the cd. This flexible pcb is a very nice solution to the earlier enamel coated wire which is much weaker. I guess it's now safe to route +ve to the uP. Another thing about this flexipcb is that it's pretty much fire proof. At first I wanted to use my soldering gun to melt away the coating but it refuse to even weaken. In the end I had to use the razor to shave away the coating. Perhaps the negative contact spring will have to be removed so there won't be extra play to stress the flexible pcb when assembling or disabling the battery. Ok, I haven't quote the price for making these but I guess it won't be too expensive. I might be able to get this printed for the micro, if I could relocate the micro to another position in the kroll. Then the other parts can also go on to the flexible pcb.
Why Kroll? I spent countless hours looking for alot of alternatives such as nylon nuts and other items that has threads but neither of them have the suitable thread I need. Customizing is out of question. The Kroll cheap and strong as an electronic host. The rubber boots is nice waterproof.
The Intelligent Kroll, is no more mechanical or technically less mechanical that people hate. However the tactile switch is still mechanical. Inside the modified kroll, house an Atmel AtTinyAvr that works all the way down to 1.8volts. During operational testing I find that works down to 1.6volts without any problem. The microcontroller switches a low resistance n-channel mosfet at variable duty(PWM) to archieve dimming. If you know which AVR I am talking about, yes it's the one without SRAM without PWM. So you know it's a pain to program. However, it's cheap and it suck little current with lowest operating voltage.
Features
A few features of the iKroll (in a ARC LSH)
ShortBurst - 10 seconds of 200ma light
FullBurst - Infinite on 200ma light
User Preset - 10ma to 330ma (10 levels, maximum drive depends on the dc2dc circuit)
Blink - blink at 100ma once every 3 second
EDIT: I should add a momentary on at full brightness for tactical use as it is important. I do not expect this switch to be used in mission critical situation as it is still in development stages. Thanks to Otokoyama for pointing out.
A short press will put the light in to ShortBurst another press brings you in to FullBurst and so on. A long press will shutdown the light in whatever mode.
A feature that I like is that the light will slowly dim to shutdown. Another feature is the Xenon burst, the light will flicker then slowly steady to FullBurst. When all stable, I am going to mod my LSH sense resistor so I can have a boost function /ubbthreads/images/graemlins/naughty.gif.
Need Improve
The Intelligent Kroll is quite dumb actually. The switching frequency for Zetex, Linear(ARC LSH) and direct drive are totally different therefore the Kroll need to be programmed specifically. Perhaps I should include three sets of different dimming frequencies into the Kroll so it can be selected when working with different type of circuits. The 2K flash memory is really preventing anymore features getting added. I need more space!
Perhaps I should switch to the new tiny13 that has PWM and it works all the way down to 1.8volts. A better solution is to switch to a totally new platform EM Microelectronic EM6680, looks very good with low 1.2volts operating voltage and PWM. However emmarin seems to be a busy company and never reply my emails and the information to program it might be scare. Perhaps the mcu is too good to be true and never exists or oo expensive for them to give out samples.
Ok this is really off topic but I have to say this /ubbthreads/images/graemlins/twakfl.gif /ubbthreads/images/graemlins/hahaha.gif
I have to thank my girl for being extremely tolerant for the pass few weeks when I work really hard. She is the most loving and yet caring person in the world.
Cheers,
Vince.
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