If its ATtiny85 or 1634 based it has a temp sensor. It was probably just removed because it will never overheat even with all 7135s enabled.
Thank you, Toykeeper. If I bridge the 6th and the 7th pads and set the stepped mode to 7 steps, will the first 5 steps be equally bright as the 5-stepped modes (like a default setting) before bridging?
I have got a BLF LT1 Rev 5.0 and soldered the pad 6 and 7 to increase the current (previously I drew a line with a pencil, but didn’t notice any difference in brightness). Still don’t feel that it’s brighter. Did I miss anything?
Pads 4 & 5 are not connected. At least on earlier versions, the lower number pads need to be connected for 6 & 7 to have an affect. Using a pencil should work, try that on 4 and 5.
Thank you for your reply. The man came to answer it himself. There have been some discussions above about the revision of this Rev 5.0, which I don’t understand. Seems like the pads 4 and 5 are connected by those little metal things between them (they talked about resistors, not sure if these are the the resistors) or that the pads 4 and 5 are not connected as you say? If it’s the latter case, that means my LT1 is running with just 3 pads? Really?
From other thread, take a multimeter to test the pads between 4 pads and 5 pads. They should be connected by the 0 ohm tiny resistor. If not connected then the 0 ohm resistors connecting either 4 or 5 may be bad and reducing power?
“As Lexel says, the latest LT1 driver should have 0Ω resistors connecting AMCs 4 & 5 as standard. You can check that with a multimeter – you should see a short-circuit between the ‘4’ contacts, and another short-circuit between the ‘5’ contacts, even though they’re not soldered.
If any of you have a new-model LT1 and a multimeter, please try it and let us know for sure Smile
The 0Ω resistors make it easier for Sofirn to manufacture and do quality control, because they’re less prone to human error compared to manually soldering contacts with a soldering iron.
If you want more output from your LT1, you still need to solder the ‘6’ contacts together yourself. If you want still more output, you need to solder the ‘7’ contacts together as well.
If you want less output, you have to unsolder the 0Ω resistors next to the ‘5’ contacts. If you want still less output, you have to unsolder the 0Ω resistors next to the ‘4’ contacts as well.
If you change your mind afterwards, you can restore higher output by soldering the ‘4’ contacts together again, and then the ‘5’ contacts together again. You don’t have to worry about saving the 0Ω resistors, so it’s not a problem if you destroy them when you unsolder them. ”
All the lower numbered pads 4 & 5 have to be bridged as well on both channels in order for the 6 & 7 pads to work when bridged.
I forgot rev 5 has the resistors, they are near the pads, labeled R_AMC4 and R_AMC5. Not sure why the left the pads, but I’m sure Lexel has a good reason for it. So if you can’t get brighter with 6 & 7 connected then I’m not sure what to suggest.
I know this will sound strange, but are you sure its not brighter? Do you have a way to measure the current from the batteries to the light? Or some sort of a meter to measure intensity? It won’t be super noticeably brighter, but really should be somewhat noticeable.
YodibearAl said it well.
I’m really thankful for all you guys’ answers. I don’t have a better way to measure the brightness other than just using my phone to measure the lux with some lux meter app in a dark room or under the bed, lol. I still got the same readings as before bridging. But I believe that the lantern’s 4 and 5 pads had been bridged from the factory because the max brightness was bright enough.
Looking at this lantern I’m interested in purchasing one. Is there going to be another group buy at all? Or can someone point me in the right direction of a good deal or coupon please?
Thanks in advance
Depends from witch country ? Lately Sofirn has bean giving discount codes for amazon usa-canada-australia . Aliexpress is the cheapest, then sofirn own shop .
I’m in the UK. Can only ship from Aliexpress without batteries (which I need) with batteries and case $67.99 from the Sofirn shop
Try pm them, could have a code for amazon uk .
The best price with batteries seems to be 60$us . Got mine today delivered by amazon for 81$can .
Sorry to be so ignorant!
Where do I pm them? do they have a presence on this forum?
May I ask where you have seen this deal?
Look for a title with Sofirn in it, find the id and clic the send pm .
A few days ago the price at sofirn shop was $60 ; the price at aliexpress is $57 . Amazon uk sells the lt1 79 pounds with local delivery . Ask them for a discount code or when it would be possible to have one ?
Try posting a request for a code for the LT1 in this thread:
Update everyone, I have been in a bit of a hiatus lately as i was diagnosed with the COVID-19 and became ill for a few weeks, and currently recovered but have a lot on my plate with life’s struggles, financial struggles, job struggles, etc. I do hope to get back to BLF as soon as i can to continue the LT1-Mini project, and future Lantern projects. 
- Dennis / DBSARlight