For reference, I assume you mean the Bestech D140 BMS
https://buildkitboards.com/products/bestech-d140-charge-only-bms
After taking a look at the product pictures for the D140, I have couple of notes that I made on the key design differences.
The D140 BMS is very, very simple. No programmable logic, everything is passive/non-programmable. Around 9-11 unique components, most likely super cheap price wise, I’m guessing around 2$ for all the passives/non-programmables, 1$ for the FETs and couple cents for the connectors. It’s built down to price and then made in big volumes. Pretty sure they have good margins on it, or at least re-seller has.
One sided component placement. Con, this means that you need more board size/space to be able to fit an equivalent amount of parts. Pro, cheaper assembly costs, due to needing to run board through SMD line only once, where as dual side component placement board needs to be run twice through an assembly line, once for each side. Interestingly they still opted to use through-hole FETs… I guess labor is cheap(er) in China.
Lack of good competition on the low-end BMS market (or higher end for that matter). Why try harder if you don’t have anyone to compete against and/or your product is selling well.
It’s a cookie cutter copy topology from their other designs.
Low-side load switch topology.
No comms of any sort. No any sort of indication of charging or balancing on the board either, or at least I didn’t spot any led anywhere.
The approach for the design of the FlexiBMS Lite was not price driven, but rather feature driven. When I started this thread I had an idea in my head for the feature set that I then presented to the forum for feedback. From there the design changed and evolved along the feedback and feature discussion.
Once the wanted features were selected and “locked in” I then started to check what the most economical approach component selections wise was to still fulfill the wanted features. Alongside the component selection I’m doing the schematic and layout design and seeing how much board space I have and If I can fit everything or even shrink the board down in size.
My BMS has a lot of high performance components with a good feature set. The board is designed from the get-go with semi-high integration density and uses a 4-layer PCB to be able to route everything. There is just a different design ethos between these two boards, mine is feature driven without so much priority on price, where as their’s is minimal features with priority on minimal cost.
I want to make a cool product, not necessarily the most profitable one, but I think making cool things will always draw some/more attention/customers then just making a dime-a-dozen product.
ayoooo) and then those samples would get averaged.
has any one made a esk8 national holiday yet for more building time.
