Analog Devices Inc./Maxim Integrated MAX6365PKA44+T

Overview

The MAX6365PKA44+T from Maxim Integrated is a low-power microprocessor supervisory circuit with battery-backup switching, chip-enable gating, and manual reset input. It operates from 1.2V to 5.5V, features a factory-preset 4.38V reset threshold (±130mV), guarantees RESET assertion down to 1.2V, delivers 150ms minimum reset timeout, and supports CMOS RAM backup in brownout conditions.

For engineers reviewing the MAX6365PKA44+T datasheet, MAX6365PKA44+T pinout, MAX6365PKA44+T application, or MAX6365PKA44+T equivalent, key selection criteria include its SOT23-8 package, open-drain active-low RESET output, 10µA quiescent current, 1.5ns CE propagation delay, and integrated VCC-to-BATT switchover control for memory retention during power failure.

Technical Context

This device integrates four core functions: precision supply monitoring with ±1.5% threshold accuracy over temperature, automatic VCC/BATT switchover with 40mV hysteresis, on-board chip-enable signal gating with 20Ω on-resistance and 1.5ns propagation delay, and debounced manual reset input with internal 20kΩ pullup.

It implements a dual-path power routing architecture: OUT sources from VCC during normal operation and switches to BATT when VCC falls below both the reset threshold and VBATT by ≥20mV. The RESET output remains asserted for ≥150ms after VCC recovers, ensuring reliable µP initialization.

Key Specifications

Pinout & Package

MAX6365PKA44+T is housed in an 8-pin SOT23 package (2.9mm × 1.6mm × 1.1mm), optimized for space-constrained portable and industrial PCBs.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar microprocessor supervisory applications.

Compared with MAX6365LKA44+T, the MAX6365PKA44+T offers identical supervision functionality with lead-free compliance, while TPS3808G33DBVR omits critical battery-switchover and CE-gating capabilities required for memory retention-making it unsuitable for applications demanding data integrity during power loss.

Availability

MAX6365PKA44+T is available at Aetrix Electronics and suitable for portable medical sensors, industrial PLC memory modules, point-of-sale terminals, and set-top box firmware storage requiring stable component supply and long-term lifecycle support.

Supply support for MAX6365PKA44+T includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Maxim Integrated (now part of Analog Devices) designs precision analog and mixed-signal ICs for power management, sensing, and connectivity in demanding industrial and automotive environments.

The MAX6365–MAX6368 product line targets space-constrained µP systems needing integrated power supervision, battery backup, and memory write protection-replacing discrete reset + switch + gating solutions with a single 8-pin SOT23 device.

FAQ

What is the exact reset threshold voltage of the MAX6365PKA44+T?

The MAX6365PKA44+T has a factory-preset reset threshold of 4.38V (typical), with a guaranteed range of 4.25V to 4.50V across temperature and supply variations. This value is laser-trimmed during production and specified in the Reset Threshold Ranges table of the datasheet. The "44" suffix in the part number directly encodes this 4.38V nominal threshold, and the MAX6365PKA44+T maintains this accuracy without external components.

Does the MAX6365PKA44+T support battery backup for CMOS RAM, and how does switchover work?

Yes, the MAX6365PKA44+T provides automatic battery backup for CMOS RAM via its integrated VCC-to-BATT switchover circuit. When VCC drops below both the 4.38V reset threshold and VBATT by at least 20mV, the internal MOSFET connects BATT to OUT. The 40mV hysteresis prevents oscillation during slow VCC decay. OUT then powers the RAM from the backup source, and the MAX6365PKA44+T continues asserting RESET to halt µP activity until stable power returns.

What is the function of the MR pin on the MAX6365PKA44+T, and does it require external components?

The MR (Manual Reset) pin on the MAX6365PKA44+T is a debounced logic input that asserts RESET when pulled low. It features an internal 20kΩ pullup resistor to VCC, so no external pullup is needed. A momentary switch from MR to GND provides user-initiated reset, and the device holds RESET active for ≥150ms after MR returns high. External RC filtering is optional but not required due to built-in noise immunity.

Can the MAX6365PKA44+T drive SRAM chip-enable signals directly, and what is the propagation delay?

Yes, the MAX6365PKA44+T drives SRAM chip-enable signals directly through its CE IN/CE OUT pair. During normal operation, CE IN passes through to CE OUT with a typical propagation delay of 1.5ns and on-resistance of 20Ω. When RESET is asserted, CE OUT is disabled-held low for 12µs if CE IN was low-to prevent partial writes. This eliminates need for external gating logic and ensures deterministic memory access control in the MAX6365PKA44+T.

What package type and RoHS status does the MAX6365PKA44+T use?

The MAX6365PKA44+T uses an 8-pin SOT23 package (2.9mm × 1.6mm × 1.1mm) and is RoHS-compliant and lead(Pb)-free, as indicated by the "+T" suffix. The "T" denotes tape-and-reel packaging, and the "+" explicitly specifies lead-free construction per JEDEC J-STD-609. It is compatible with standard SMT reflow profiles up to +260°C peak temperature.