Four-rail supervisor with programmable thresholds
The LTC2900-1IMS#PBF from Analog Devices monitors four supply voltages simultaneously, issuing an active-low reset when any rail falls below its programmed threshold. Sixteen selectable threshold combinations cover common voltage pairs without external resistor dividers, which simplifies BOM and layout. The open-drain output stays asserted for a minimum of 5 ms after all rails return to tolerance, giving the downstream processor time to stabilize.
Four monitored channels let you cover core, I/O, memory, and auxiliary rails with one IC — no need for a second supervisor or discrete comparator string. The 16 selectable threshold combinations mean the same part number can be used across multiple board variants by changing a pin-strap resistor, reducing line-item count in the BOM. The 5 ms minimum reset timeout is long enough to ride through supply glitches from hot-swap events or load transients, but short enough that the processor doesn't hang waiting for a power-good signal. Open-drain output allows wired-OR connection to a shared reset line with other supervisors or a manual reset button.
The 10-MSOP package (3.00 mm width) fits on dense PCBs alongside fine-pitch BGAs and small-passive arrays. Surface-mount assembly is standard for reflow processes.
ROHS3 compliant, so it passes European and California regulatory checks without an exemption review.