Analog Devices Inc./Maxim Integrated MAX6429AGUR+T

Overview

MAX6429AGUR+T from Maxim Integrated is a factory-trimmed, single-output, low-power battery monitor IC for Li+ and multi-cell alkaline/NiMH/NiCd systems. It features a fixed low-threshold of 2.9V (±2.5%), high-threshold of 3.0V (±2.5%), 140ms LBO timeout, 1µA typical supply current, and operates from 1.0V to 5.5V. It delivers active-low push-pull LBO signaling for system-level low-battery warning in portable medical devices and MP3 players.

For engineers reviewing the MAX6429AGUR+T datasheet, MAX6429AGUR+T pinout, MAX6429AGUR+T application, or MAX6429AGUR+T equivalent, this page provides verified threshold values, SOT23-3 package mapping, LBO timing behavior, and real-world use cases with design-meaning context - all confirmed from Maxim's official datasheet Rev 2 (12/05).

Technical Context

The MAX6429AGUR+T implements a dual-comparator hysteresis architecture with internal 615mV reference (used indirectly via factory-trimmed thresholds), precise voltage monitoring logic, and a guaranteed 140ms minimum timeout on LBO deassertion. Its BATT-supplied operation eliminates need for external VDD regulation.

It uses a single push-pull LBO output referenced to BATT, asserting low when battery voltage falls below VLTH = 2.9V and deasserting only after BATT rises above VHTH = 3.0V and remains stable for ≥140ms - preventing false triggers during transient recovery.

Key Specifications

Pinout & Package

MAX6429AGUR+T is housed in a lead-free 3-pin SOT23-3 package (JEDEC MO-178AA), footprint-compatible with industry-standard SOT-23 footprints and optimized for space-constrained portable designs.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar battery monitor applications.

Compared with MAX6429AGUR+T, MAX6428AGUR+T offers earlier low-battery detection but identical architecture and integration, while TLV7031DBVR demands external components to achieve comparable functionality - increasing design risk and board area.

Availability

MAX6429AGUR+T is available at Aetrix Electronics and suitable for portable medical devices, MP3 players, and pagers requiring stable component supply with guaranteed long-term manufacturability and consistent electrical performance.

Supply support for MAX6429AGUR+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) is a semiconductor company specializing in precision analog, mixed-signal, and power management ICs for industrial, medical, and consumer applications.

The MAX6427–MAX6438 family was designed specifically for ultra-low-power, high-accuracy battery state monitoring in space- and energy-constrained portable electronics - delivering factory-trimmed or user-adjustable thresholds with integrated hysteresis and timeout logic.

FAQ

What is the exact low-battery threshold voltage for MAX6429AGUR+T?

The MAX6429AGUR+T has a factory-trimmed low-threshold (VLTH) of 2.9V ±2.5%, meaning the LBO output asserts when battery voltage falls below 2.8275V (min) and remains asserted until BATT rises above 3.0V ±2.5% (2.925V min) and sustains that level for ≥140ms. This value is confirmed in Maxim's datasheet Table 1 (AG code) and Electrical Characteristics section.

Does MAX6429AGUR+T require an external voltage reference or resistors?

No. MAX6429AGUR+T is a factory-trimmed device with internal precision thresholds and requires zero external components. Unlike adjustable variants (e.g., MAX6433), it draws power directly from BATT and delivers a ready-to-use push-pull LBO signal - eliminating resistor dividers, references, and timing capacitors needed in discrete comparator solutions.

What package type and pin count does MAX6429AGUR+T use?

MAX6429AGUR+T uses a 3-pin SOT23-3 package (JEDEC MO-178AA), with pin 1 = BATT, pin 2 = LBO, and pin 3 = GND. This compact, surface-mount package measures 2.92mm × 1.3mm × 1.0mm and is compatible with standard SOT-23 pick-and-place and reflow processes.

Can MAX6429AGUR+T operate down to 1.0V battery voltage?

Yes. MAX6429AGUR+T is fully specified to operate and deliver valid LBO logic states down to BATT = 1.0V, as stated in the Absolute Maximum Ratings and Electrical Characteristics tables. This enables reliable end-of-discharge detection for single Li+ cells, which typically fall to ~2.5V nominal but can reach 1.0V under heavy load or aging.

How does the 140ms timeout function in MAX6429AGUR+T?

The 140ms timeout in MAX6429AGUR+T is a built-in timer that prevents LBO deassertion until BATT remains above the high threshold (3.0V) for ≥140ms. This ensures microcontrollers or DC-DC converters are not re-enabled during transient voltage rebounds - a critical feature for stable system recovery in portable electronics with pulsed loads.