Analog Devices Inc./Maxim Integrated MAX6428EHUR+

Overview

MAX6428EHUR+ from Maxim Integrated is a single-output, factory-trimmed battery monitor IC with internal hysteresis for Li+ and multi-cell alkaline/NiMH/NiCd power supplies. It features a fixed low-threshold of 2.8V (±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 output to signal battery depletion in portable medical devices and pagers.

For engineers reviewing the MAX6428EHUR+ datasheet, MAX6428EHUR+ pinout, MAX6428EHUR+ application, or MAX6428EHUR+ equivalent, this device supports low-power system state management-enabling graceful shutdown, low-power mode entry, and noise-immune battery status detection without external components.

Technical Context

The MAX6428EHUR+ integrates a precision voltage reference, comparator, and timing circuitry to implement dual-threshold hysteresis monitoring on a single BATT input. Its push-pull LBO output drives directly into microcontroller NMI or enable inputs without pull-up resistors.

Thresholds are factory-trimmed and temperature-compensated across –40°C to +85°C, with guaranteed valid logic down to BATT = 1.0V. The 140ms minimum timeout prevents false triggering during transient voltage recovery after load removal.

Key Specifications

Pinout & Package

MAX6428EHUR+ 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 space-constrained portable designs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6427EHUR+, MAX6428EHUR+ provides higher trip points for improved noise margin in alkaline systems; compared with TLV7031DBVR, it delivers production-ready, calibrated hysteresis monitoring with zero external components and guaranteed timing behavior.

Availability

MAX6428EHUR+ is available at Aetrix Electronics and suitable for portable medical devices, pagers, electronic toys, and legacy cell phones requiring stable component supply, long-term lifecycle support, and lead-free compliance.

Supply support for MAX6428EHUR+ 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, sensing, and interface applications in industrial, medical, and consumer markets.

MAX6428EHUR+ belongs to the MAX6427–MAX6438 family of ultra-low-power battery monitors - engineered specifically for reliable, component-free state signaling in battery-critical portable electronics.

FAQ

What is the exact low-battery threshold voltage of MAX6428EHUR+?

The MAX6428EHUR+ has a factory-trimmed low-threshold voltage (VLTH) of 2.8V ±2.5%, and a corresponding high-threshold (VHTH) of 3.0V ±2.5%. These values are laser-trimmed during production and guaranteed over –40°C to +85°C. The MAX6428EHUR+ uses these fixed thresholds to assert its active-low push-pull LBO output when BATT falls below 2.8V and hold it asserted until BATT rises above 3.0V and remains there for ≥140ms.

Does MAX6428EHUR+ require external components to operate?

No, MAX6428EHUR+ requires no external components. It is a self-contained battery monitor with integrated reference, comparator, and timing circuitry. The MAX6428EHUR+ draws power directly from the BATT pin, asserts LBO based on internal thresholds, and provides a push-pull output that drives directly into microcontroller inputs - eliminating pull-up resistors, capacitors, or voltage dividers.

Can MAX6428EHUR+ operate with a single 1.5V alkaline cell?

Yes, MAX6428EHUR+ operates down to BATT = 1.0V, making it compatible with single 1.5V alkaline cells - though its 2.8V/3.0V thresholds are optimized for 2-cell alkaline (3.0V nominal) or single Li+ (3.6V nominal). For single alkaline, consider MAX6433–MAX6435 variants with user-adjustable thresholds scaling down to ~0.62V.

What is the function of the LBO pin on MAX6428EHUR+?

The LBO pin on MAX6428EHUR+ is an active-low push-pull output that asserts (drives low) when the monitored BATT voltage falls below 2.8V, and deasserts (drives high to ≥0.8×BATT) only after BATT rises above 3.0V and remains stable for ≥140ms. This pin directly interfaces with µP NMI, reset, or enable inputs without external biasing - a key feature distinguishing MAX6428EHUR+ from open-drain alternatives.

Is MAX6428EHUR+ RoHS-compliant and lead-free?

Yes, MAX6428EHUR+ is lead-free and RoHS-compliant. The "+" suffix in the part number explicitly denotes lead-free packaging per Maxim Integrated's ordering convention. It is supplied in tape-and-reel format and qualified for reflow soldering per JEDEC J-STD-020.