Nanjg AK-47A based lantern mode selection

Bra_Ljus · 2019-03-15T07:18:27.000Z

Hej,

the last of the four set-ups I’m testing is based on the Nanjg AK-47-A from Mountain Electronics, purchased without any of the offered code for complex modes. I connected a SPST latching push-button switch and fully charged battery. I have not messed with any of the four stars on the back side to set mode groups.

When I press the button on the switch and the switch has latched to make a permanent connection, the LED goes into a “strobe” mode and remains there. Is this the expected behaviour? Can I not set the driver to continuous illumination? Or must I select one of the mode groups by soldering from one or more of the stars to minus? Mountain Electronics only says this:

- Mode groups (default AK-47A firmware):

- 3 Mode. Low-Medium-High

- 5 Mode. Low-Medium-High-Strobe

With the default AK-47A firmware, you select mode groups by waiting for the light to blink on the low mode, then turning off the light or pressing the switch directly after the blink

The “strobe” mode I see means the LED blinks 3-4 times per second, so I guess that’s not the “low mode”. In any case, no switch button presses after connecting the battery changes anything apart from “strobe” or OFF.

Thanks for any hints!

MtnDon · 2019-03-15T14:56:31.000Z

The “SPST latching push-button switch” is either on or off, right? There is no momentary contact or break ability, right? When it is OFF and you press it down it clicks and changes to ON and stays there. Right? Then does the reverse when pressed and clicked again?

The driver needs a momentary disconnect in the power supply leads to the driver in order to switch between Low, Medium and High, or Low, Medium, High and strobe. That switch you have probably does not permit that. Perhaps if you press and switch the light off and then back on rapidly enough you may be able to make the brightness level change. If you can not do that with the switch you should be able to make a brightness change by quickly disconnecting and reconnecting one of the wires in the power circuit.

The driver is meant to be used with a reverse clicky switch as is found in many off the shelf tube lights that have tailcap switches.

Bra_Ljus · 2019-03-15T15:53:31.000Z

Thanks, the switch is either ON or OFF (although when the button is only half-depressed, it makes a contact eventually). So, in that sense, I can make it contact “momentary” for very brief periods, but that changes nothing. All my Nanjg AK-47A also “strobe” when no switch is in the circuit at all.

Is a “reverse clicky switch” a latching SPST NO with “momentary off”?

Neither at Farnell, Digikey, Mouser, Conrad, Reichelt, etc. there is a “clicky switch” category, so what type of switch would I need to order from there, if a latching SPST switch is the wrong type?

Your “wire switch” idea sounds good, I try that - although making contact that way is like my very brief “momentary” button presses above.

Also, how would I do that “you select mode groups by waiting for the light to blink on the low mode, then turning off the light or pressing the switch directly after the blink” when that “low mode” never appears?

MtnDon · 2019-03-15T18:56:33.000Z

mtnelectronics sells assorted switches; reverse and forward clicky both on and off tailcap style boards.

mtnelectronics.com

Switches

I have looked for this type of switch at Mouser, Digi-key, etc and have never managed to find any. Maybe I have not searched properly, I don’t know. There are switches available on Aliexpress and the other Asian sites that sell flashlights. Ebay sellers too.

In case you are not certain the forward clicky are the type where, when starting from OFF, a slight press turns on the light but when the switch button is released the light goes off again. That makes them handy for signally dit-dot sort of thing.

Starting from OFF, a reverse clicky does nothing when pressed until the switch clicks AND you begin to release the button. Then the light turns ON. Once ON, a momentary press breaks the circuit and if the driver firmware is “looking”for that interruption it follows the program, usually to move up or down the brightness range.

I believe the standard nanjg47 firmware has memory activated. When a brightness level is ON for more than a few seconds, the firmware remebers that once the switch is turned OFF. Often the memory does not apply to strobes, but I am not fully aware of how the basic nanjg47 is setup. Maybe someone else will chime in here.

Perhaps if you get the driver turned on you can cycle through the levels and see if you can make the light stay in low, or medium. Let the light be on in any constant brightness for at least 2 or 3 seconds. Then turn off and after a few more seconds apply power once again. The light should come back on in the same level if all is okay.

Bra_Ljus · 2019-03-15T18:56:48.000Z

Good grief, how daft was I? I wired the switch in the secondary side and I know not to switch SMD or COB LEDs on the constant current side. Well, I let the image above stand exemplary for my old age senility!

So, MtnDon, when I now try your “bare wire switch” approach, I have modes - having connected the two rightmost stars looking from below, that should be the LO/MID/HI mode. Seems not to be the case, but it’s almost working…

MtnDon · 2019-03-15T19:21:52.000Z

Bra Ljus:

having connected the two rightmost stars looking from below, that should be the LO/MID/HI mode. Seems not to be the case, but it’s almost working…

I am not sure that the stars on the board are supposed to do anything at all with the standard default firmware? But I am not at all sure how the default is supposed to function.

It appears to me that there are only two choices, with made "by waiting for the light to blink on the low mode, then turning off the light or pressing the switch directly after the blink." as shown on the mtnelectronics page. Just two modes, one with strobe and one without. I don't have any of those drivers at hand with the default firmware otherwise I'd give it a try.

MtnDon · 2019-03-15T19:26:06.000Z

Also, you mentioned connecting two stars…. If the stars are to ber used for mode setting, I believe the process is to connect a star to the ground ring on the perimeter of the driver board, not connect two stars to each other. A little blob or thin layer of solder is all that is needed to bridge the star to the ground/negative ring.

Bra_Ljus · 2019-03-15T20:18:04.000Z

Thanks!

Aliexpress, etc. all take three weeks to Europe and I want to finish the last of my four lantern set-ups next Wednesday, because then I want to order parts for 30 lanterns and want to decide which of them all is best for the purpose.

Now that I realised my big mistake the SPST latching switch I bought is the right type, so I can buy a good looking one from Farnell or Digikey already.

The stars do something, but not quite what others have written with regards to the basic already flashed three-modes I’m after. I guess I just have to try different star combinations, ha!

I did what you wrote; I soldered the two leftmost stars to the outer ring individually, then the two rightmost stars. I get all sorts of mode combinations - high, slow pulse, low, strobe, mid, etc. so I think it’s just a case of star-rim-soldering-combinatorics LOL!

Why I want to use this driver is that it does not get as hot as costly “professional” ones and I have the suspicion I get more than three hours of full brightness from this set-up, compared to the other drivers I tested so far (entirely different topology, based on a TI chip and inductor, etc. with solder-unfriendly QFN packages - and five times as costly).

This is fun!

MtnDon · 2019-03-15T21:01:37.000Z

I’ve used that nanjg driver on a few projects, usually with one of the optional firmware sets that mtnelectronics offers or with something I flashed myself. You are so right… this is a fun hobby! I have added a couple of the 7135 regulators on one project and removed one or two on others, all to chnage the highest output level.

Have fun, I’m glad it is working for you.

staticx57 · 2019-03-15T21:19:41.000Z

I have not seen it explicitly mentioned yet but the switch goes in between the power source and driver. Not between the driver and LED.

MtnDon · 2019-03-15T21:59:34.000Z

Yep. I did not take time to look over the wiring carefully at first as I was on an very old small screen mobile. Now that I am on a big screen it is easier tosee and note that the switch may not be in the actual power supply side. At least nothing went up in smoke.

What is the little PCB the battery connects to?

Bra_Ljus · 2019-03-15T23:16:21.000Z

MtnDon:

Have fun, I’m glad it is working for you.

Ha! Yes, but no cigar… yet. Need to try all star solder combinatorics tomorrow ; )

Bra_Ljus · 2019-03-15T23:21:44.000Z

MtnDon:

What is the little PCB the battery connects to?

That’s the Li-Po charger with USB and load-sharing/power-path, so the lantern can be on while the battery is recharging. Also comes in a 1000mA charge-rate flavour. There are surely Chinese knock-offs, but they would take ages to get here. The Adafruit stuff so far has been very reliable.

Bra_Ljus · 2019-03-15T23:23:34.000Z

staticx57:

I have not seen it explicitly mentioned yet but the switch goes in between the power source and driver.

Yeah, mentioned that in an earlier post. That was daft and while fiddling with modes, I did not even realise that that was the issue. Facepalm worthy ; )

Moa_the_student · 2019-11-01T09:24:22.000Z

Hej!
As a project, I have been designing a luminaire where I used this driver (Nanjg AK-47A from Mountain Electronics). I’m totally new with electronics, but have manage to set the driver into the low-medium-high mode, but there’s no OFF mode. To be able to turn off the led I had to connect an additional switch connected to the battery. Of course, this is not optional. Does anyone know what I have been doing wrong? I have tried to figure it out, but my knowledge in electronics are way to basic… I would be so grateful for help!

Maybe I’m using the wrong switch?
Maybe it’s not the right mode?

Note: I have the exact same setup as the picture on the top.