Do-it-yourself LED headlamp flashlight. DIY LED headlamp - homemade - do it yourself - diagrams
Greetings to all mysku readers! Today I want to talk about how I redid the headlamp. All improvements are quite universal and can be applied to other flashlights.
Since the idea to arrange everything in the form of an overview came to me after the file and soldering iron were picked up, some of the original photographs can no longer be taken. However, the site has similar reviews without alterations, you can read or.
So, what the Chinese sent: in a nice, neat box there are two chargers, from the network and a car charger, and the lantern itself. 
First, about charging. The network one has a standard minimum of details, so there is not much to say about reliability and quality. Its actual characteristics: voltage without load 4.17 volts, current under load approximately 0.4A (at short circuit 0.48A). 
As for the automobile, then things are even worse! Two resistors, one limits the current of the LED, the other, as conceived by the Chinese, is a complex current / voltage stabilizer, in accordance with the current-voltage characteristic of the charge lithium battery(sarcasm). If no jokes, then I advise you to either immediately throw out such a charge, or remove it away from accidental use. 
Now the forehead. Structurally, it consists of the flashlight itself and a separate battery compartment. The compartment is designed for two 18650 batteries connected in parallel, they are also suitable with protection, but not with a flat positive contact (more on this below, in revision). The same compartment houses the driver and charging socket. The driver has 2 brightness modes, 1.3A and 0.27A on the diode, and a strobe. The type of work is selected by sequential enumeration of all modes plus shutdown. 
The lantern looks to be of good quality. The lens moves with sufficient effort, there are no backlashes. There is a vertical adjustment with fixed positions. Now about the world. He, in my opinion, is rather cold, a little blue.
This was the data of objective control, now about what obviously does not suit me. First, the temperature of the light. It feels like the native diode shines at 7000K, I will replace it with. It is a neutral white, somewhere between warm and cold. It’s impossible to take a normal photo for comparison, the colors are not the same, but still I’ll post what happened.
Two diodes under a white sheet.
On the right is the one that was, on the left is the replacement.
Pill. In the original, it was like this: the star on which the LED is installed barely touched the pill itself. As you can see, the thermal contact is simply scanty, besides, there was no paste.
I solved this problem with the help of an aluminum disk, the size of which is the inner diameter of a pill, which I screwed to the LED star (the photo of the assembly will be below). Driver. The "folk" on the ATtiny13A microcontroller with 8 AMC7135 current stabilizers was taken as the basis.
Each stabilizer is designed for a current of 350mA, and since they are connected in parallel, the total current is 2.8A. The brightness is controlled by PWM. Initially, the microcontroller firmware contains several sets with operating modes. You can select a suitable set of modes by soldering the desired sprocket to a common contact. A description of all modes can usually be obtained from the seller of the driver. I went a little further. It was decided to slightly modify the driver and change the firmware with the modes. A detailed refinement methodology can be read on the website and on. I'll tell you briefly. The main goal is to increase efficiency, remove unnecessary strobes, change brightness modes. We cut two tracks and solder two jumpers. 
Next, we program the microcontroller, for this you need either a programmer via USB, or a small device for COM port. I didn’t really want to order and wait a month for a ready-made programmer, especially since it was necessary for one time, so I decided to solder a fixture for COM. The faint of heart should not watch!
Scheme 
fit 
I do all my one-time crafts by hanging installation. Just a habit
I miss the soldering details, the programming process, this is a rather large topic, it is better to arrange it separately, you can read about it in detail at the links above, I can only say that I did this procedure for the first time and I didn’t have any questions, all the nuances are painted on the same flashlight. So, what happened in the end: a driver with one set of 5 brightness modes
2.8A
1.05A
0.35A
0.16A PWM
0.01A PWM
The choice of the mode is carried out by short-term power off. There is a memory of the last state.
Ask why do I need 5 brightness modes ?? This is a philosophical question, and I'm not ready to answer it yet. Those who do not need such a set can choose any other firmware for their needs. By the way, the current in the maximum mode can be reduced if you cut the track to the control output of the current stabilizer. According to the principle, one disabled stabilizer is minus 350mA from the maximum brightness mode.
I decided to write a new driver together with an LED in one pill, since there is a place. Assembly view. 
The wire connecting the flashlight to the battery compartment was also replaced. True, nothing good came across at hand, so I made it myself. I took 2 MGTF wires and placed them in heat shrink. 
If someone doubts the advisability of such a replacement, I will give an example: with the same length, with a current of 3A, the voltage drop on the native wire is 0.8 volts, on my homemade one - 0.16V. In practice, this threatens with an early transition of the flashlight to a reduced brightness mode.
Battery compartment.
In order to charge the batteries directly in the compartment, I decided to use a special one. 
The thing is very cheap and at the same time comfortable. Of the features: it has a charge indication, the ability to set the charge current with a selection resistor, as well as mini USB connector for external memory. The value of the resistor 1.2k was immediately set corresponding to a current of 1A. By changing this value from 10k to 1.2k, you can change the charging current from 0.13A to 1A, respectively. This may be relevant if used as a memory USB port laptop, or low-power mains charging.
Pickup resistor
After testing, the following data was obtained: sanyo battery The 2600 was charged from the initial 3.1V to 4.21V in about 3 hours.
Next is the power button.
Here the biggest problem arose - the lack of space inside the compartment. I wanted to put something like this in ordinary flashlights, but the dimensions of such switches are too large, and smaller options do not provide a working current (I remind you that I have 2.8A). Therefore, it was decided to use not a button, but a mini switch. A USB hub for 7 ports was launched for donor organs, small switches are just used there, one for each port. A fresh review of such a hub is just below. Not without a file here.
Returning to the positive contact of the battery holder. It is deep enough recessed and because of this, the battery with a flat plus does not reach the contact. Everything is simple here, I cut the spring from the driver into two halves (it is no longer needed there anyway) and soldered it to the positive contacts of the holder.
General view of the compartment after completion. 
Instead of two LEDs on the module board, I put one two-color LED on the case. True, the patch came out again, I needed an LED with a common anode, but in the household I found only one with a common cathode. I had to do this: instead of native LEDs, I put jumpers, soldered two anodes (green, red) of my two-color diode directly to the microcircuit terminals, and connected the common cathode to the negative contact. Everything is working!
Ready lamp assembly. 
Beamshots can't be done, so sorry.
Let's summarize. After all the changes, it turned out approximately what I wanted. The only drawback is the insufficient surface area for cooling the LED and nothing can be done about it. The driver itself is quite efficient, although it heats up, but does not need additional cooling. You cannot keep it at maximum brightness for a long time. For those who just want to buy and use this model I will not advise, and vice versa, I will advise those who like to disassemble, finish, improve something. Choosing this model of a lantern, I expected in advance that I would finish it myself according to my requests. For me it's like a hobby. This is where I will end my story. I expect constructive criticism.
A long time ago, when there were no LED headlamps in Russia at all, and the petzl tikka had not yet appeared, the first experiments of underground walking on white LEDs appeared ...
When the petzl tikka appeared, the question arose of how to make a lantern better and cheaper, because. tikka except for the size everything else - there was one big drawback ...
That's when this flashlight was made, the only difference is that now it has survived the reincarnation and the LED module has been replaced in it from 6 Nichia NSPW500BS to 1 Cree XR-E Q5 + some forced improvements.
Thus, the body of the lantern lived for 7 years of operation, including speleology and speleology, digging, patrol and even snorkeling in the sea ... Experience has been accumulated about the lack and design improvements, which will be presented in this text.
In spite of:
despite the fact that some structural elements should be implemented differently - and moreover, there is experience of their correct implementation - they are mostly absent in the photographs, because this lantern was redone in 1 hour, and there is no more permanent one than a temporary one - and the temporary one is already 1 year old.
Corps and appearance:
I remind you once again - the case is 7 years old:
The body of the lantern "Alturs Mini" was taken as a basis, with the only difference that it was necessary to greatly shorten its lantern part, because. initially it is designed for a lamp and has a fairly deep reflector. To do this, you need to use a construction knife and cut off the plastic thread, after sawing off the "trunk" to the desired depth.
Of the advantages of the case is: normal thick glass, normal plastic, tilt adjustment, battery compartment at the back of the head. Minus - we eliminated the long nose.
I also noticed a small minus of the standard elastic band, which tends to stretch and crawl through the clamps - I did it easier, I sawed off the regular clamp (reducing the lever), and simply sewed on the strap. However, the adjustment remained - i.e. the strap can be adjusted in the latches on the battery compartment.
To fasten the wire along the sling, plastic fittings are used; regular holders turned out to be not very convenient, because. designed for one thick wire.
The foam on the back is regular and quite comfortable.
About wires:
this is a very important part of the lantern. I used to use MGTF - an excellent wear-resistant wire in fluoroplastic insulation, stranded and flexible. I highly recommend using it (or better). In order for the two wires not to “walk” and not move apart, it is necessary to make a heat shrink ring 0.5-0.8 cm wide every 4 cm to fit the wires to each other. In the middle, the wire was fastened with fittings to the sling. I do not consider it necessary to make a one-piece heat-shrinkable and single wire. difficult to repair, and also does not make sense - the fluoroplastic wire is quite difficult to damage (from experience - the wire went along the edge of the helmet during the caving expedition - no complaints and subsequent replacement).
The photo uses stranded wires from the old PC power supply - simply because at the time of the upgrade the MGTF was over. However, they lasted a year.
In the very head part there is such a pie:
heatsink-thermal paste-heatsink-thermal paste-led-insulator-reflector
Because metal reflector - in order not to short out inconveniently located terminals on the LED, it is necessary to use an insulator (plastic washer, impregnated paper, etc.).
Thermal paste can be replaced with hot melt adhesive - then you can not use fastening screws - this is up to you.
Special part: the radiator must come out of the case to the outside.
The radiator was also made from aluminum plates of an old PC power supply. In the body of the lantern part, four holes were melted - two on the side, two more in the back wall - through which the plates were brought out and bent so as not to interfere. Other variations on the theme are possible, such as a nice copper heatsink at the back of the headlamp, as is often done on commercial versions. You can use thermotubes ... There is a lot of room for imagination. My example shows only what you can do with your own hands from what is at hand.If removed protective glass and a cover, as well as a reflector - then we can easily get to the diode itself.
I didn’t particularly bother with the centering of the diode, because a reflector is applied, i.e. there is no difference - +/-5 mm to the side.
Of course, the view is not glamorous ... On the other hand, for 7 years ... If there is a desire, then you can clean all the elements of excess thermal paste, center the LED ...
Instead of a thread, an adhesive film is used. Usually I glued the protective cap (which holds the protective glass) to the glue: a second + a primer for ABS plastic - it held up very well. But in this version of the flashlight, I needed the ability to quickly shoot / install a reflector. The film simply allows you to fix the protective cap - nothing more.
Tip: tie the wires inside the lamp unit into a knot so that during sharp jerks there is no load on the soldering. If the place does not allow, then you can only hope for a coil of wire on the sling retainer.
Using a drill, we make a hole at the bottom of the battery compartment - we insert a button there. We pre-solder it, and only then we glue it (or screw it in) - it depends on the design of the button.Previously, there was an excellent Soviet MT-1 toggle switch, but then there is no room for 4xAA batteries in the battery compartment. At the time of the alteration, I needed to use exactly this number of batteries. If you manage to find a good driver for power supply from 3xAA or 1xLiON, then there will be enough space in the compartment for MT-1 for sure ...
You also need to pay attention to the wires again - in my case it was done incorrectly: the wire exit from the battery compartment must be additionally protected - a simple solution - heat shrink in two layers - one layer 3-4 cm wide, the second over the first 2-3 cm wide - place in the place where the wire rubs against the edges of the case. As practice has shown, an unprotected wire is frayed in about 6-9 months of dense operation. In the right case - in a double shrink knot, the wire is well protected from chafing against the case, and in a single one, the flexibility of the design is restored - which reduces the likelihood of damage to the wire from bending it out of the thick layer of heat shrink together, if we applied one, but thick layer of heat shrink.
Types of battery compartment. An adapter for batteries or batteries is sold in stores and costs about 30-40 rubles.
In the place where the electrical tape appeared - there should be heat shrinkage, but it was already necessary to go out - and it was molded in haste ...
The main point here is perhaps one - the wire exit from the battery adapter - the wire is frayed at the metal ring on the block - the solution is old and simple - heat shrink in one layer ..Inside, near the wall, you can see the stabilizer under which there is a button.
I don't want to touch on stabilizer problems - because. This is discussed in other forum threads. I just want to note that in this moment I use a linear stabilizer for 5 modes: turbo-norms-minimum-strobe-sos, and as batteries 4x Ni-NH batteries with a capacity of 2500-2600mAh.
In addition to everything, I would like to say that it is desirable to select a reflector as shallow as possible - this will allow you to create a wide beam of light, but nevertheless with a focus in the middle ... I really like this kind of light - because. I see everything in front of me, as well as in the distance due to the focus ... If you need a sharp beam, then vice versa
PS. As a result, we get a flashlight on the LED Cree Q5, with 5 modes of operation. Excessive in brightness for cave caves, turbo mode (mainly used for other purposes), and practical "normal" and "min" light modes.
In my article I will tell you how to make an insanely bright battery led lantern, and turn night into day with your own hands.
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Most of us use flashlights on camping trips, for night walks, or just when we go out into the dark. Usually we buy these lights in hardware stores, and they shine quite dimly. To remedy this, I designed and built a heavy-duty flashlight that is suitable for lighting the road at night, creating cool photo and video effects (like glowing spheres in science fiction), lighting a job site and much more, all at a reasonable cost.
Step 1: Materials Used
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I give a list of the materials I used, you can take the same or pick up something similar.
- switches
- Lithium polymer batteries 11.1V (take those that suit your flashlight best), I give you links to suitable models:
You will also need wires, a terminal block, fuses and fuse holders, solder, heat shrink, etc.
The resulting long-range flashlight will come out about three times cheaper than store-bought counterparts. And do not forget that the battery and Charger can be used in other devices. Also, during the assembly of a hand lamp, you will gain new knowledge and experience, and this is priceless.
Step 2: The main working points of the assembly of the lantern
Since the diode in our spotlight consumes a huge amount of energy, up to 100 W (33 V and 3 A), it gives off a lot of heat, so it needs a serious heat sink. The one I listed on my list may seem too big to you, and it is, but our flashlight itself is "too much."
To provide energy for this "beast" you will need a powerful battery, for devices with high power consumption, it must also be light and compact, because after all, we are making a portable flashlight - lead-acid ones immediately disappear. Lithium polymer batteries meet these requirements. These are usually installed on drones and RC models. They are small, light and can be quickly discharged - just what we need for our flashlight. I installed a 11.1V battery in my flashlight (link above).
Since the battery power is 11.1V, and the diode needs 33V, we took a boost converter. It uses a built-in potentiometer to step up the 11.1V input voltage to 33V output. You must ensure that the diode does not receive more than 34V, and not less than 26V. In order to monitor the output voltage of the converter, you will need a digital volt-ammeter. It shows you the voltage and current going to the diode. All this allows us to adjust the brightness of the light and helps prevent the current from being supplied too high voltage. For additional protection we will install 4A fuses at the inverter output. No matter how fun it is to blow up a 100W diode, I don’t want to wait for delivery again.
A discharge indicator is necessary to prevent deep discharge, and due to the sensitive internal chemistry of lithium polymer batteries, such an indicator is necessary. Each battery cell will be charged at a voltage of up to 4.2V per cell, and not lower than 3V. If the voltage drops below 3V, it will quickly drop to 1V, which will damage the cell. We will prevent this by setting the discharge indicator to 3.2V (you will hear sound signal) using the button above. But if, for some unknown reason, the voltage drops below 3.2V, quickly charge the battery to the lowest charge level, this will allow the battery cell to be restored with minimal damage.
In my flashlight, I installed two switches - one, the main one, for general power, the second - only for the diode. I did this so that when the light is off, the cooling system, the discharge indicator and the digital voltammeter continue to work. This way I can see the voltage in the battery with the light on or off, and I also enjoy listening to my appliance making noise when the main switch is turned on.
Step 3: Mount the Diode to the Heat Sink
To start the installation, apply thermal paste to the diode as shown in the picture above (since the use of thermal paste has a lot of conflicting reviews, you can not do this). After that, I screwed an aluminum heatsink that I had lying around with screws to the diode, and fixed them to a large heatsink, as in the other picture above.
Be careful not to overtighten the nuts to avoid bending the diode.
You can glue the reflector lens at this point using epoxy.
Step 4: Body
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I took the body from an old broken lantern. First I took out its contents - two car headlight bulbs and two small lead-acid batteries. Then I slightly modified the body to fit the new content. For this I needed: hot melt adhesive, epoxy resin, sandpaper and an engraver.
First I removed some calipers with an engraver. Then I pre-assembled all the parts and attached the wires to the reflector, I cut off the excess wire length later. In such cases, epoxy always helps. Now you need to try how the assembled parts fit in the case, everything fit perfectly for me. I then cut the cooler vents and covered them with a piece of grille from an old broken iPod speaker. I also cut and sanded holes for the digital voltammeter, discharge indicator, main switch and trim pot, and installed them and the boost converter using a lot of hot glue because it is not visible inside the case.
Then I added a few finishing touches - Velcro fasteners on the battery and on the flashlight handle, so that it was convenient to attach it to something, and glued the stickers that came with the battery. Now it's time to do the wires.
I think not everyone will have the luxury of having a flashlight housing ready to go, and I'm very interested in how you solve this problem.
Step 5: Wiring
I sketched a primitive wiring diagram in the lantern. When you wire the light, leave the wires long enough to fit the size of the body. I connected most of the wires before I put everything in the case, but you can place the components first and then run the wires, it depends on the body of your flashlight.
At this point, you will need a ground and power terminal block, wires (12 or 14 US gauge for high power connections), a 4A fuse and fuse holder, and other small items.
Be sure to cover all connections with heat shrink. First, solder the wire to the socket of the XT60 connector, connect the switch in series with the ground wire, this switch will be the main switch. Then secure the ends into the terminal block, creating a positive and ground line (depending on the terminal block you are using, you may need to run wires from each connection to the terminals).
Boost Converter
Solder the power and ground wires to the inputs.
Connect the switch to the fuse holder and connect to the negative output. Here we will connect a 4A fuse.
To adjust the voltage going to the diode, you will need access to a potentiometer. For this, I brought the tuning potentiometer already available in the converter into access.
Digital voltammeter and diode
Connect two thin wires (red to positive, black to ground) to power the terminal block. Connect the larger black wire to the negative output of the boost converter, after the fuse holder.
The yellow wire will go to the negative output of the diode. The larger red wire will go to the positive output of the boost converter.
discharge indicator
To connect a discharge indicator, connect the balance connector from ground to third, cut the ground wire and connect to the main ground connector on the terminal block.
Step 6: What not to do
Here is a list of things NOT to do.
Electronic tricks for inquisitive children Kashkarov Andrey Petrovich
3.11. What can be done at home from a "head" lamp?
On sale are Chinese LED headlamps (up to 24 pcs.) Lanterns with phased switching on and even flashing mode. It is very uncomfortable. Two positions would be enough - on (all) / off. How to do this, we will consider further.
A portable headlamp marked Bailong BL-536 with 3 AA (LR6) batteries (and similar) can be purchased almost everywhere today; the difference is only in the cost and price "cheats" of intermediaries.
The interiors of the flashlight are not striking in their diversity: a battery compartment, two boards and a miniature tact button (non-latching microswitch) SDTM-630-N, which controls the operating modes of the flashlight:
1st press – 4 LEDs are on;
2nd press - 4 more (total 8);
3rd press – all LEDs are lit (12);
4th press - all LEDs flash at a frequency of approximately 2 Hz;
The 5th press turns off all LEDs, then everything repeats again.
The printed circuit board with the LED matrix is designated XG-12-4; on it there is a microassembly “flooded” with a drop of the compound. Its internal circuit reacts to the closing of the contacts of the microswitch (at the end of the flashlight body) in the trigger mode - one closing of the contacts (no matter how long) turns on a certain mode, each subsequent one turns on the next one, and so on in a cyclic algorithm.
The control pulse for the microassembly is negative, that is, the trigger is triggered by the negative edge of the input pulse, or by a short to “-” power supply.
The contacts of the microassembly are not marked on the board in any way. In headlamps of a similar purpose (with a different number of LEDs, but in the same case), I have seen printed circuit boards with different markings, track layouts and the number of LEDs, so detailed diagram there is no special meaning, because it is possible that the reader will not find exactly the same version of the lantern anywhere else (but others will).
I think that such "toys" are assembled in China by several hundred small manufacturers by hand, as Volvo cars were once assembled in Sweden; in small batches and therefore did not always turn out identically, the same applied to spare parts.
For the same reason, it makes no sense to modify the device by supplementing the logical electrical circuit with the participation of a new trigger, which would have only 2 control modes LED matrix th, so cherished in dreams by some readers - pressed 1 time - the light is on, pressed the second - the light went out. But it is in this particular example that such improvements, in my opinion, are doubtful in terms of their final effectiveness; if there is absolutely nothing to do...
Given the above arguments, as well as the small cost of the flashlight itself and the lack of free space for the board (microcircuit) of refinement, such an undertaking had to be abandoned, and act in a radical way.
Next, consider the option for specific model headlamp with 12 LEDs (for a different number of LEDs, or a different type, you will need to make adjustments to the resistance of the limiting resistor - more on that below).
A radical improvement of the device comes down to replacing the non-latching SDTM-630-N button (other variants of the tact button may also be found) with an almost similar one - with a fixation of the PS700L, PS645L, PS850L type (cost 12–18 rubles), where the numbers in the designation indicate the size buttons, for example, PS700L - 7 mm ..
So, we disassemble the body of the flashlight and take out the battery pack.
Having unscrewed 2 self-tapping screws with a Phillips screwdriver, we take out the board with the microswitch; it is marked as XGCL-21.
Soldering regular button(flexible leads into the holes of the board) and instead we install a microswitch with fixing the position of the PS700L type.
By the way, in this case, the button with fixation from the control panels of old (10-year-old) car radios is perfect in size.
The next step is to make changes to printed circuit board with an LED matrix (it is even easier to remove it from the lamp body - through the glass lens of the lamp).
All LEDs must be connected in parallel to each other using flexible mounting jumper wires of the MGTF-0.6 type. The printed conductors leading to the microcircuit are cut off.
Into the gap of the simplest electrical circuit(4.5 V battery - latching microswitch - LED array) include a 24 ohm ±10% fixed resistor to limit the current in the circuit (4.5 V directly applied to the LED array will cause a large (unacceptable) current, which will lead to the failure of the LEDs), and in this case it is not necessary to create a switching current stabilizer for the above arguments (“sheepskin is not worth the candle”).
The resistance of the limiting resistor is calculated according to Ohm's law so that the voltage drop across it is 2 ... mA).
Therefore, the simplest recommendation in terms of time, details and, ultimately, efficiency, is to change the mode microswitch to a similar one - in appearance, but with position fixation, for example, on the PS700L; it has 6 contacts, 2 of them are “cut off” with wire cutters before being installed into the board in a regular place (with 4 holes).
Well, of course, in view of the foregoing, it is necessary to "work" with the printed conductors on the LED matrix, taking into account the above recommendations.
Now the “Chinese gadget” works as you like, without tiring of “extra” modes, and its appearance has not changed. It would be necessary to send this remark to the Celestial Empire.
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