What the 1.665V threshold and 140 ms timeout mean for your rail
The MAX6834VXRD3: This 140 ms window covers the power-up settling time of most 1.8 V-core logic and mixed-signal ICs — the processor or FPGA finishes its internal POR sequence before the supervisor releases the reset. The open-drain output lets the supervisor share a common reset bus with other devices or pull to a different voltage than the monitored rail. A pull-up resistor to the logic supply is required; the output sinks current when reset is active.
Analog Devices lists the MAX6834VXRD3 as an active part. The part is marked RoHS non-compliant per the manufacturer listing. Verify your assembly's exemption or alternative if RoHS compliance is required.
Package and temperature grade
The SC-70-3 footprint is shared with many other supervisors from Analog Devices and competitors, simplifying last-minute BOM swaps without a board spin. The 1.665 V threshold targets 1.8 V nominal rails common in low-power MCUs and FPGAs.