PW-13 · Chapter 4 · Power Conversion
Software-set bias from −2.5 V to +2.5 V
A test fixture must bias a sensor element at any voltage from −2.5 V through 0 to +2.5 V, set by software, sourcing or sinking up to 50 mA. Design the supply.
| Level | ●●● onsite design / senior |
| Track | Power |
| Really testing | Recognizing that normal regulators can't do this. |
Full worked answer: in the book, page 108 — what to say first, how to explain it, the numbers worth quoting and the follow-ups. About the book →
Going deeper
Extra explanation that is not in the book: worked numbers, where people go wrong, and how to say it in the room.
Going deeper for this question is coming.
Errata
Correction: Worst-case output-stage dissipation corrected from 0.25 W to about 0.38 W (sourcing at −2.5 V or sinking at +2.5 V). Fixed before the first printing. All errata
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