*BLF LT1 Lantern Project) (updated Nov,17,2020)

I’m interested put me on list please

Dannyboyy added to the interest list at number 952.

*Ok some updates: Barry contacted me earlier and they are in need of a base driver circuit design, and asking about the UI (i’m guessing the firmware for the lantern, which i believe Toykeeper is working on that)
I don’t know who designed the circuit board for the Q8, but we are in need of something for the planned two-channel tint ramping, Their engineers are held up on these components at this time, for them to continue they need some basis for what were looking to achieve for the tint ramp & charging system. Without a board design or someone who can help us with that… the only other option is to revert back to using the Q8 board modded with 4-7135s and no tint ramping or charging feature or USB feature. Any input on this form anyone here woudl be greatly appreciated as it seems were held up without a finalized driver board design to incorporate the tint ramping feature, charging feature, & USB power bank feature.*

What’s about DELs driver?
From here *BLF LT1 Lantern Project) (updated Nov,17,2020) - #736 by DEL

I’d forget about the tint ramping and just put some nice 3 or 4000k emitters in it, and call it a day. Strayed too far off the original plan from two years ago IMO. Nice ramping UI, some nice quality emitters and get on with the project.

What he said.

That could be the option right now to get this into production faster. Then maybe down the road a version-2 could be designed with more options.

Or an aftermarket driver upgrade like most of us usually do anyway.

It’s about 90% done but no one seems to know how to do the other 10%.

If the lantern uses a Q8 driver as the base, it needs these changes at minimum:

  • Replace the FET with 4x7135 chips. (or 5x7135)

In order to get tint ramping, it also needs these changes:

  • Replace the original 1x7135 chip with 4x7135 chips. (or 5x7135)
  • Split the LED- pad in half so there is one pad per power channel.

And to get USB charging, using an external board, it should also have some other small changes:

  • Add BAT+ and BAT- pads (CHG+ and CHG-) which connect the charge circuit directly to the batteries.

These are all fairly straightforward changes, so I’m optimistic that they can happen.

:+1: Simple is best

Seems we have too many Indians and not enough Chiefs

I’m interested on this lantern, please put me on the list.

I’m not any good at designing the driver circuitry, but if anyone has Eagle or KiCAD schematics already of the relevant circuit parts, and measurements for the driver board, I could layout a PCB for it.

Just followed that link to the DEL board. What else needs to be done with that? I looked at his OSH Park drivers collection, and that one isn’t present. Does anyone have a copy of it or know how to get a copy? Where is DEL anyway? He’s been gone for almost a half a year? What happened?

No one can find a copy of that board, or we would have been done ages ago. Not sure what happened to DEL, but he is MIA for now.

I am designing the driver presently, and it is near completion. I am using Eagle. I am not terribly good at this, so if you have Eagle and would not mind checking out the present state I would appreciate it. PM me your email if you are interested.

PM sent! Thanks!

Toykeeper maybe forward that information to Barry so he can inform the engineers who are working on the lantern production prototype that it can be modified that way. I already sent them the LED pad 2-channel design for that part.

I got my right hand today hurt bad
But I can try to get it, hopefully the antibiotics wirk or they ha e to cut my right pointer ng finger open and I will be handicapped a lot longer

Problem is what is U3 for?
No files to start wirh so modding my Q8 driver

Lexel, DEL describes the driver board a little bit in post 736. After the images, at the bottom of the post, it tells what U3 is among other things. Here’s the relevant text:

From here:

U3 is a precision DC opamp and does the closed-loop current control for the LED driver (driving a meaty FET in linear mode). A sense resistor creates the feedback signal. The MCU (a venerable tiny85) generates the reference signal. Driver dropout should be < 150 mV, giving regulated control down to about 3.2 V.
U4 is an all-in-one power-bank chip from TI’s BQ24 or BQ25 series (currently looking at the BQ25895, it is also used in the higher end Xiaomi power banks).