Analog Devices Inc./Maxim Integrated MAX6365HKA46+

Overview

MAX6365HKA46+ from Maxim Integrated is a low-power microprocessor supervisory circuit with battery backup, chip-enable gating, and factory-preset 4.63V reset threshold. It provides active-high open-drain reset output, monitors VCC down to 1.2V, switches CMOS RAM supply between VCC and backup battery during brownout, and gates CE signals with 1.5ns propagation delay. Used in portable POS terminals and industrial controllers requiring reliable power-fail response.

For engineers reviewing the MAX6365HKA46+ datasheet, MAX6365HKA46+ pinout, MAX6365HKA46+ application, or MAX6365HKA46+ equivalent, key selection criteria include its 4.63V reset threshold tolerance (±0.13V), 150ms minimum reset timeout, 10µA quiescent current, and SOT23-8 package compatibility with space-constrained µP systems.

Technical Context

The MAX6365HKA46+ integrates four core functions: precision VCC monitoring with hysteresis, automatic VCC-to-battery switchover when VCC falls below both reset threshold and VBATT, on-board chip-enable signal gating with transmission-gate architecture, and debounced manual reset input. Its internal 20kΩ MR pullup enables direct switch connection without external components.

It operates across -40°C to +85°C with guaranteed RESET/RESET validity down to 1.2V supply, supports 1.2V–5.5V VCC range, and delivers 150mA from VCC or battery via low-on-resistance MOSFET switching (4.6Ω typical at 2.38V). The device uses a fixed 4.63V reset threshold with ±0.13V accuracy over temperature.

Key Specifications

Pinout & Package

MAX6365HKA46+ is housed in an 8-pin SOT23 package (2.9mm × 1.6mm, 0.95mm height), optimized for high-density PCBs and reflow-compatible lead-free assembly.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6365PKA46+, the MAX6365HKA46+ offers open-drain flexibility for level translation and bus sharing, while TPS3808G33DBVR trades battery backup and CE gating for lower cost and quiescent current in simpler power-monitoring tasks.

Availability

MAX6365HKA46+ is available at Aetrix Electronics and suitable for industrial PLCs, portable medical monitors, POS terminals, and set-top boxes requiring stable component supply with long-term lifecycle support.

Supply support for MAX6365HKA46+ 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 interface applications in industrial, automotive, and computing markets.

The MAX6365–MAX6368 family was engineered specifically for µP-based systems needing integrated power supervision, battery backup, and memory write protection in minimal footprint-targeting portable, battery-powered, and mission-critical embedded equipment.

FAQ

What is the exact reset threshold voltage of the MAX6365HKA46+?

The MAX6365HKA46+ has a factory-trimmed reset threshold of 4.63V, with a guaranteed range of 4.50V to 4.75V over temperature (-40°C to +85°C). This value is fixed and not user-adjustable, making it suitable for precise +5V supply monitoring where 3% tolerance is acceptable. The "46" suffix in the part number explicitly denotes this 4.63V threshold variant.

Does the MAX6365HKA46+ support battery backup functionality, and how does it switch?

Yes, the MAX6365HKA46+ fully supports battery backup. It switches OUT from VCC to BATT when two conditions are met: VCC falls below the 4.63V reset threshold and VCC drops at least 20mV below VBATT. A 40mV hysteresis prevents oscillation during slow VCC decay. In backup mode, OUT sources from the higher of VCC or BATT, delivering up to 150mA with typical 4.6Ω on-resistance at 2.38V.

What type of reset output does the MAX6365HKA46+ provide, and how should it be interfaced?

The MAX6365HKA46+ provides an open-drain active-high RESET output (Pin 1). It requires an external pull-down resistor to establish a logic-low default state. When asserted, RESET goes high (open-drain pulled up by external circuitry); when deasserted, it floats. This configuration enables wired-OR connections, level shifting, and compatibility with µP reset inputs expecting active-high signaling.

How does the chip-enable (CE) gating function work on the MAX6365HKA46+?

The MAX6365HKA46+ gates CE signals using a low-on-resistance transmission gate between CE IN (Pin 2) and CE OUT (Pin 8). During normal operation, CE IN passes directly to CE OUT with 1.5ns propagation delay. When reset asserts, CE OUT is held low for 12µs to complete pending memory accesses, then actively pulled up to OUT. This prevents erroneous writes to SRAM during power faults.

Is the manual reset input (MR) on the MAX6365HKA46+ debounced internally?

Yes, the MR input (Pin 4) on the MAX6365HKA46+ includes internal debouncing-no external RC network is required. It features a 20kΩ internal pullup to VCC and responds to logic-low assertions with guaranteed timing: reset remains asserted for ≥150ms after MR transitions from low to high. This simplifies mechanical switch integration and improves noise immunity in industrial environments.