Three-rail window supervisor for automotive ECUs
It monitors three independent voltage rails, each with a 0.8V threshold, and asserts an active-low reset when any rail falls outside the window. The reset output is open-drain, so it can be wire-ORed with other supervisors or pulled up to the appropriate logic voltage for the downstream MCU or SoC.
Thresholds and reset timing for rail sequencing
All four threshold inputs are set at 0.8V — this is a fixed internal reference, not adjustable. The part is designed for low-voltage core rails (e.g., 0.8V, 1.0V, 1.2V) where the supervisor must detect undervoltage before the logic fails. The reset timeout is 10ms typical, which gives the power supply time to recover from a transient before the system is held in reset. This is shorter than many simple reset ICs (e.g., the TLV803EA29VDBZR has a 130ms minimum timeout), so the TPS37043 is better suited for fast-recovery rails where a long reset delay would stall the system.
TSOT-23-8 footprint and temperature range
Housed in a TSOT-23-8 package (SOT-23-8 variant), the device occupies minimal board area — roughly 2.9 mm × 2.8 mm — which is valuable in dense automotive modules where every square millimeter counts. The wide range also suits industrial applications where the ambient temperature exceeds the commercial 85°C limit.