What this reset IC does and where it fits
The Analog Devices MAX6422XS44+T is a Simple Reset/Power-On Reset IC that monitors a single supply voltage and asserts a reset signal when the monitored voltage drops below the 4.375 V threshold. It delivers an active-high, push-pull output — meaning the reset pin goes high when the supply is out of tolerance — and supports an adjustable/selectable reset timeout period via an external capacitor. The part is rated for the -40°C to 125°C industrial temperature range, making it suitable for environments where the board sees thermal cycling: engine control modules, outdoor base stations, or factory-floor PLCs. Packaged in a 4-lead SC-70 (SOT-343), it fits tight PCB layouts where board space is at a premium.
4.375 V threshold — what it means for a 5 V rail
The 4.375 V threshold is the trip point at which the reset asserts. The reset timeout is adjustable via an external capacitor.
Active-high output — verify polarity before layout
Most reset supervisors in this class drive an active-low open-drain output. The MAX6422XS44+T is different: its push-pull output goes high on a fault. That means the reset signal is high when the supply is good and low when it is not — but the active-high reset output is the signal that goes high during reset. Confirm that your processor or FPGA reset input expects a high-true signal. If your design uses a low-true reset, you will need an inverter or a different part.
Lifecycle and sourcing posture
The MAX6422XS44+T carries an Active product status with ROHS3 compliance. No end-of-life notice or last-time-buy window is in effect.