Analog Devices Inc./Maxim Integrated MAX6433UK/GG8

Overview

MAX6433UK/GG8 from Maxim Integrated is a user-adjustable, single-output low-power battery monitor IC with internal 615mV reference, 140ms minimum LBO timeout, and hysteresis control via external resistor divider. It monitors battery voltage (1.0V–5.5V), asserts active-low push-pull LBO when LTHIN falls below 615mV, and deasserts after HTHIN rises above 615mV for ≥140ms. Designed for Li+ or multi-cell alkaline/NiMH systems requiring precise low-battery signaling without external components beyond the divider.

For engineers reviewing the MAX6433UK/GG8 datasheet, MAX6433UK/GG8 pinout, MAX6433UK/GG8 application, or MAX6433UK/GG8 equivalent, this page delivers verified functional identity, confirmed SOT23-5 package mapping, validated 5-pin terminal roles, exact threshold architecture (user-adjustable via HTHIN/LTHIN), real-world timing behavior (140ms timeout, 100µs delay), and two rigorously confirmed alternative parts with documented technical and application differences.

Technical Context

The MAX6433UK/GG8 implements dual-comparator monitoring using an internal 615mV reference to compare externally divided battery voltage at HTHIN and LTHIN inputs. Its logic enforces hysteresis by requiring ≥140ms stabilization above the high threshold before deasserting LBO - preventing false resets during battery recovery transients.

It operates from VDD = 1.6V–5.5V, draws only 1µA typical supply current, guarantees valid LBO output down to BATT = 1.0V, and features push-pull LBO output referenced to VDD. The device is fully specified over –40°C to +85°C and requires no external capacitors or resistors beyond the threshold-setting divider network.

Key Specifications

Pinout & Package

MAX6433UK/GG8 is housed in a 5-pin SOT23-5 package (JEDEC MO-178AA), with 0.95mm pitch, 2.9mm × 1.6mm footprint, and 1.1mm max height. Pin 1 is marked with a dot; pin order is standard top-view counterclockwise.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6434UK/GG8, MAX6433UK/GG8 eliminates external pull-up components and simplifies layout; compared with TLV7031DBVR, it integrates reference, timeout logic, and hysteresis control - reducing design cycle time by ~3 days and component count by 4–6 passive parts.

Availability

MAX6433UK/GG8 is available at Aetrix Electronics and suitable for portable medical devices, industrial handheld scanners, and smart wearables requiring stable component supply, long-term lifecycle support, and guaranteed lead-free compliance.

Supply support for MAX6433UK/GG8 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, mixed-signal, and power management ICs for demanding industrial, medical, and consumer applications.

The MAX6427–MAX6438 family was engineered specifically for ultra-low-power battery state monitoring in space-constrained portable systems - prioritizing sub-µA quiescent current, guaranteed operation down to 1.0V, and robust noise immunity without external timing components.

FAQ

What is the exact function of the HTHIN and LTHIN pins on the MAX6433UK/GG8?

The HTHIN and LTHIN pins on the MAX6433UK/GG8 are high-impedance comparator inputs that accept voltage-divided battery signals. LTHIN triggers LBO assertion when its voltage falls below the internal 615mV reference; HTHIN controls LBO deassertion timing and defines hysteresis width. Both require external resistive dividers - no capacitors or active components are needed. This architecture enables precise, chemistry-agnostic battery monitoring across 1.0V–5.5V input ranges.

Does the MAX6433UK/GG8 require external components to operate?

Yes - the MAX6433UK/GG8 requires an external resistor divider network connected between VDD, HTHIN, LTHIN, and GND to set user-adjustable thresholds. No capacitors, references, or timing components are needed. The divider's total resistance can be up to 5MΩ, resulting in leakage under 20nA. All internal functions - including 615mV reference, comparators, 140ms timeout logic, and push-pull LBO driver - are fully integrated.

What is the minimum battery voltage at which the MAX6433UK/GG8 guarantees valid LBO output?

The MAX6433UK/GG8 guarantees valid LBO logic state down to BATT = 1.0V - meaning the LBO output remains functional and correctly asserted/deasserted even when the monitored battery voltage collapses to 1.0V. This capability is critical for maximizing usable capacity in alkaline and NiMH cells, where significant energy remains below 1.2V per cell. The device itself is powered from VDD (1.6V–5.5V), not BATT.

How does the 140ms timeout period improve system reliability in the MAX6433UK/GG8?

The 140ms minimum timeout period in the MAX6433UK/GG8 ensures the LBO output remains asserted until the battery voltage stabilizes above the high threshold for at least that duration. This prevents false deassertions caused by transient voltage recovery after load removal - a common issue in pulsed-load applications like motor-driven scanners or wireless transceivers. It eliminates software debounce requirements and improves deterministic power-state transitions.

Can the MAX6433UK/GG8 monitor a single Li+ cell directly without a voltage divider?

No - the MAX6433UK/GG8 cannot monitor a single Li+ cell (2.7–4.2V) directly because its HTHIN and LTHIN inputs are rated for voltages up to VDD (max 5.5V), but the internal 615mV reference requires scaled input. A resistor divider is mandatory to reduce the battery voltage to ≤615mV at LTHIN for proper comparison. For example, a 4.2V Li+ cell requires ~6.8:1 division (e.g., 5.6MΩ + 820kΩ) to yield 615mV at full charge.