Analog Devices Inc./Maxim Integrated LMX339HASD+T

Overview

LMX339HASD+T from Maxim Integrated is a quad, open-drain, low-voltage comparator with internal 2mV hysteresis, designed for noise-immune threshold detection in automotive and portable systems. It operates from 1.8V to 5.5V, delivers 140–430µA total supply current (depending on VDD), supports –40°C to +125°C operation, and features rail-to-rail input common-mode range including ground. It is used in battery-monitoring circuits where slow-moving or noisy input signals require stable output transitions.

For engineers reviewing the LMX339HASD+T datasheet, LMX339HASD+T pinout, LMX339HASD+T application, or LMX339HASD+T equivalent, key selection criteria include guaranteed hysteresis, wide supply voltage range, automotive temperature rating, open-drain output compatibility with mixed-voltage logic, and SO-14 package suitability for space-constrained industrial PCBs.

Technical Context

The LMX339HASD+T implements four independent comparators using submicron CMOS process technology, enabling low offset voltage (≤9mV over full temperature range), low input bias current (±400nA max), and high PSRR (60–70dB). Its internal hysteresis is fixed at 2mV and remains stable across temperature and supply voltage variations.

Each comparator features rail-to-rail input stage with no phase reversal under overdrive, open-drain NMOS output capable of sinking up to 73mA at 5V (15mA at 1.8V), and output saturation voltage as low as 35mV at 1mA sink current. Propagation delay is 90–200ns depending on overdrive and supply voltage.

Key Specifications

Pinout & Package

LMX339HASD+T is housed in a 14-pin SOIC (Small Outline Integrated Circuit) package, 8.65mm × 3.91mm × 1.75mm body size, RoHS-compliant, with standard 1.27mm pitch.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar quad open-drain comparator applications.

Compared with LM339DR and TLV339IPW, the LMX339HASD+T uniquely combines guaranteed internal hysteresis, automotive temperature rating, and true pin compatibility with legacy LMV339 - enabling drop-in noise immunity upgrades without layout changes or external component additions.

Availability

LMX339HASD+T is available at Aetrix Electronics and suitable for battery management systems, automotive body electronics, industrial sensor interfaces, and portable medical devices requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for LMX339HASD+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 U.S.-based semiconductor company specializing in precision analog, mixed-signal, and power management ICs for industrial, automotive, and communications markets.

The LMX339HASD+T belongs to Maxim's LMX339H family of hysteresis-equipped comparators, engineered specifically for robust threshold detection in electrically noisy, thermally demanding environments where reliability outweighs raw speed.

FAQ

What is the purpose of internal hysteresis in the LMX339HASD+T?

The LMX339HASD+T integrates 2mV of internal hysteresis to prevent output oscillation when input signals are near the switching threshold - especially critical for slow-moving or noisy inputs like thermistor readings or battery voltage ramps. This eliminates the need for external positive-feedback resistors, simplifying design and improving board-level noise immunity without sacrificing accuracy.

Can the LMX339HASD+T operate from a 1.8V supply?

Yes, the LMX339HASD+T is fully specified and guaranteed to operate from 1.8V to 5.5V. At 1.8V, it draws only 120–200µA total supply current, maintains 2mV hysteresis, and delivers usable output sink current (15mA), making it ideal for modern ultra-low-power systems powered by single-cell Li-ion or energy-harvesting sources.

Is the LMX339HASD+T pin-compatible with the standard LMX339ASD+T?

Yes, the LMX339HASD+T is pin-compatible with the LMX339ASD+T and shares identical SO-14 footprint and pin functions. The 'H' suffix denotes inclusion of internal hysteresis; all other electrical and mechanical characteristics - including supply range, temperature rating, and output structure - remain unchanged, enabling direct replacement to add noise immunity.

What is the maximum sink current capability of each output in the LMX339HASD+T?

Each open-drain output of the LMX339HASD+T can sink up to 73mA at VDD = 5V and 15mA at VDD = 1.8V, with output saturation voltage as low as 35mV at 1mA. This allows direct driving of LEDs, small relays, or logic inputs without external buffer transistors - provided the external pull-up resistor is sized appropriately for the load and voltage level.

Does the LMX339HASD+T support rail-to-rail input operation?

Yes, the LMX339HASD+T supports an input common-mode voltage range from –0.1V to VDD–0.7V, which includes ground and extends close to the positive rail. This enables direct interfacing with 0V-referenced sensors (e.g., current-sense amplifiers, thermistors) and eliminates the need for level-shifting circuitry in single-supply applications.