AN-11 · Chapter 2 · Analog & Op-Amps
NTC front end for a battery pack
An e-bike battery pack has twelve NTC thermistors taped across its cell modules, read by the BMS microcontroller's 12-bit ADC. Design the front end. Which ADC specs matter? Should the top of each divider come from the 5 V buck, a 3.3 V LDO, or a 2.5 V reference?
| Level | ●●● onsite design / senior |
| Track | General board |
| Really testing | Ratiometric design and choosing the specs that matter. |
Full worked answer: in the book, page 54 — what to say first, how to explain it, the numbers worth quoting and the follow-ups. About the book →
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