Three-voltage watchdog in a SOT-23-8
The Maxim Integrated MAX6725KAYDD3-T is a three-channel multi-voltage supervisor that monitors up to three supply rails and asserts a system reset when any monitored voltage falls below its threshold. It is a precision voltage monitor for multi-rail designs — think FPGAs, SoCs, or mixed-signal boards where the core, I/O, and auxiliary supplies each need an independent trip point. The three monitored thresholds are 0.788 V, 2.188 V, and one adjustable input. The reset timeout is a minimum of 140 ms. Both an active-low and an active-high reset output are available, both open-drain. That means you can wire the active-low to the CPU reset pin and the active-high to an enable pin on a power sequencer or a PLD — no extra inverter needed. The open-drain outputs also let you OR-wire multiple supervisors onto a single reset line.
Package and rework — SOT-23-8 realities
Surface-mount only — no through-hole variant. The SOT-23-8 footprint is standard, so board layout is straightforward. Keep the sense traces short and direct to the monitored rail's local decoupling capacitor to avoid noise injection on the threshold comparators.
Temperature grade and environment
Rated for the industrial temperature range of -40°C to 85°C, this supervisor suits outdoor telecom cabinets and factory-floor controllers.
RoHS status — a BOM constraint
This part is marked RoHS non-compliant. That means it uses lead-bearing solder terminations or internal die-attach materials exempted under certain categories. If your assembly line is RoHS-only with no exemption, this part cannot go through a lead-free reflow profile — it would require a segregated, tin-lead process or a manual hand-solder station. Check your BOM's environmental compliance requirements before committing the line.
Sourcing posture
No LTB window to manage, no forced last-buy — this part is a safe choice for new designs as long as the RoHS constraint is acceptable.