Recent content by curious

It will probably work but I would suggest buying a123 pack from cellman if you want lifepo4 chemistry. Much better odds of getting few years of reliable service from those cells.

They have comparable (lowish) energy density to a123 26650 but without electrical and mechanical robustness of a123 cylindricals. And the price difference is not that much either. Not sure they make much sense. OTOH if HK offered us pre-built packs of a123 20ah prismatics that would have been a...

I assume you are going DIY route. What chip do you want to use to detect the HVC threshold ? Is it HVC only or HVC/balancer ? I can probably help you interface the chip output to the signaling chain.

You mean transistor only or transistor/comparator version ? Transistor-only chain will not be accurate enough for HVC/balancer application (even if it can be designed). Comparator-transistor chain can be modified fairly easily for HVC/balancer apps. I think fechter and Gary already have few...

My wife rides slow and gentle, it is perfect for her needs. However when I try to ride it - the front spins when starting at full throttle (even on a dry pavement). Otherwise handling is not affected.

Here is another EbikeE that I built for my wife. Shot in the process of charging with the balancer attached (you can see bunch of white LEDs on the top of the battery).

That is exactly how it works, except the top cell which needs to be mirrored (there is no voltage "above" the top cell to make it exactly the same). It gets a bit tricky when the transistor goes below Vce saturation (typically around 0.15-0.25V) and the gain starts dropping which leads to chain...

I have finally built and tested this LVC-lite circuit for a 16s A123 pack. The pictures from this thread were lost so here is another one: As I said before it is not as precise as multi-TC54xx chain but for a123 lifepo4 cells the LVC detection accuracy is quite adequate. The circuit is...

Does this common wisdom of bicycle wheel building really translate well to the large diameter hubs like x5 or HS/HT ? I am not so sure. Every broken spoke on my 26" x5 wheel (and there were many) failed at the nipple because of wrong entry angle at the rim. Radial gives perfect entry angle and...

LTSpice. It is a nice completely free SPICE simulator with graphical front end supported by Linear Technology.

Warning, the following post is for perfectionsists and analog circuitry fans only :) Here is the temperature compensated version with the ideal/regular top segment (not practical as it requires extra power supply for current source I1). It is quite accurate and can be used for analog...

About 4uA, good for few decades, perhaps more...

No, it is split more or less evenly, not exceeding single cell voltage, certainly not full pack voltage. The top segment sources current proportional to the cell voltage which is propagated along the chain. This current causes equal voltage drop across resistors at each stage. If any stage sees...

I've been toying around with current-mode chaining of LVC circuits in the simulator recently and realized that you can build a super-cheap LVC using just one TC54 chip and current mode transistor chain as a sensor/aggregator. It will not have the same threshold accuracy and temperature stability...

What I was wondering is what is the voltage at the 431 output when its reference input is held above the threshold? Is it equal to 2.5V (reference) or does go to near-zero like on TC54xxx ? This determines value of load resistor and power dissipation split. BTW if you worry about individual...