Analog Devices Inc./Maxim Integrated MAX6429MQUR+T

Overview

The MAX6429MQUR+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 2.0V (±2.5%), high-threshold of 2.7V (±2.5%), 140ms minimum LBO timeout, 1µA typical supply current, and operates from 1.0V to 5.5V supply. It is used in portable medical devices to trigger low-power mode when battery voltage drops below threshold.

For engineers reviewing the MAX6429MQUR+T datasheet, MAX6429MQUR+T pinout, MAX6429MQUR+T application, or MAX6429MQUR+T equivalent, this page delivers verified electrical parameters, SOT23-3 package mapping, confirmed dual-threshold hysteresis behavior, and real-world timing constraints - all critical for battery-state decision logic in space-constrained, ultra-low-power designs.

Technical Context

The MAX6429MQUR+T implements a precision comparator-based monitoring architecture with internal 615mV reference and built-in hysteresis. Its fixed thresholds are laser-trimmed at wafer level, eliminating external resistor networks and ensuring ±2.5% accuracy over –40°C to +85°C.

It asserts an active-low push-pull LBO output when BATT falls below 2.0V and deasserts only after BATT rises above 2.7V and remains stable for ≥140ms - preventing false triggers during transient load recovery or battery voltage bounce.

Key Specifications

Pinout & Package

MAX6429MQUR+T is housed in a lead-free 3-pin SOT23-3 package (JEDEC MO-178AA), with 1.3mm × 0.8mm footprint and 0.95mm height - optimized for PCB area-constrained portable applications.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6429MQUR+T, MAX6428LQUR+T offers earlier low-battery detection for margin-sensitive alkaline systems, while TLV7031DBVR demands significant external circuitry to approximate basic hysteresis and timing - making MAX6429MQUR+T superior for production-ready, minimal-BOM battery monitoring.

Availability

MAX6429MQUR+T is available at Aetrix Electronics and suitable for portable medical devices, cell phones, pagers, and electronic toys requiring stable component supply across extended product lifecycles and seasonal demand fluctuations.

Supply support for MAX6429MQUR+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 high-performance analog, mixed-signal, and power-management ICs for industrial, medical, and portable applications.

The MAX6427–MAX6438 family was designed specifically for ultra-low-power, single- or dual-threshold battery state monitoring in space- and energy-constrained portable electronics - prioritizing accuracy, zero-component simplicity, and robust transient immunity.

FAQ

What is the exact low-battery threshold voltage of the MAX6429MQUR+T?

The MAX6429MQUR+T has a factory-trimmed low-threshold voltage (VLTH) of 2.0V with ±2.5% tolerance over –40°C to +85°C. This value is laser-trimmed during manufacturing and does not require external calibration. The MAX6429MQUR+T asserts its LBO output when the BATT voltage falls below this threshold, and the assertion remains active until BATT rises above the high-threshold (2.7V) and sustains that level for ≥140ms.

Does the MAX6429MQUR+T require external resistors or capacitors to operate?

No, the MAX6429MQUR+T requires no external components. As a factory-trimmed device in the MAX6427–MAX6432 series, it integrates precision voltage references, comparators, and timing circuitry internally. Only three connections are needed: BATT, GND, and LBO. This eliminates resistor-divider networks, timing capacitors, and associated layout sensitivity - simplifying design and improving long-term reliability of the MAX6429MQUR+T.

What is the function of the 140ms timeout period in the MAX6429MQUR+T?

The 140ms minimum timeout period in the MAX6429MQUR+T ensures the LBO output remains asserted for at least that duration after BATT rises above the high threshold (2.7V). This prevents premature deassertion during transient voltage recovery - such as when a load is removed and battery voltage rebounds briefly before settling. The MAX6429MQUR+T uses this delay to guarantee stable supply conditions before enabling downstream power converters or microprocessors.

Can the MAX6429MQUR+T operate with a 1.0V supply voltage?

Yes, the MAX6429MQUR+T guarantees valid LBO logic state down to BATT = 1.0V, as specified in the Absolute Maximum Ratings and Electrical Characteristics tables. While its operating voltage range is 1.0V to 5.5V, functionality (including correct LBO assertion/deassertion timing and output drive strength) is maintained across this full range. This makes the MAX6429MQUR+T uniquely suited for deep-discharge monitoring in alkaline/NiMH systems where usable voltage extends below 1.2V.

Is the LBO output of the MAX6429MQUR+T push-pull or open-drain?

The LBO output of the MAX6429MQUR+T is active-low push-pull. It actively drives low (≤0.4V at 3.2mA sink) when asserted and actively drives high (≥0.8 × BATT at 800µA source) when deasserted - eliminating the need for an external pull-up resistor. This configuration simplifies interface with BATT-referenced logic and improves noise immunity compared to open-drain alternatives. The MAX6429MQUR+T does not include an open-drain variant in the SOT23-3 package.