Three-rail supervisor in SOT-23-8
The MAX6729KALTD3 is a multi-voltage supervisor monitoring three independent supply rails — thresholds set at 3.075V, 4.625V, and one adjustable channel — with a single active-low reset output. The push-pull output drives directly into a microcontroller reset pin without an external pull-up, and the 140ms minimum reset timeout gives the downstream logic time to stabilize after the last rail comes up. The three-channel monitoring in this footprint means a single IC replaces what would otherwise require three separate reset generators or a larger supervisor in a bigger package.
Voltage thresholds and channel assignment
The 3-channel count is the key spec: if your board has three distinct power domains that need sequencing or brownout detection, this part handles them in one SOT-23-8 footprint. The active-low reset output stays asserted until all three monitored voltages rise above their respective thresholds and the 140ms timeout expires. This glitch-free startup behavior prevents the processor from trying to execute code before the power supply is fully settled.
Note that this part is listed as RoHS non-compliant. If your assembly requires RoHS exemption documentation or a lead-free alternative, confirm the compliance requirement before committing the BOM line.