STMicroelectronics LM339D

Overview

LM339D from STMicroelectronics is a low-power quad voltage comparator in SO14 package, designed for single-supply operation from +2 V to +36 V (or ±1 V to ±18 V dual supply), with 1.1 mA typical supply current, ±1 mV typical input offset voltage, and rail-to-rail input common-mode range including ground. It drives TTL, CMOS, and MOS logic directly and is used in voltage monitoring, window detection, and analog-to-digital interface circuits.

For engineers reviewing the LM339D datasheet, LM339D pinout, LM339D application, or LM339D equivalent, key selection criteria include input offset voltage stability over temperature, output sink capability at 4 mA, common-mode input range down to ground on single supply, and compatibility with legacy 5 V and 15 V industrial control systems.

Technical Context

The LM339D uses PNP-input transistor pairs enabling input common-mode voltage down to ground even under single-supply operation. Its open-collector outputs support wired-AND logic and level translation across voltage domains without external pull-ups required for basic functionality.

Each of the four comparators operates independently with no internal inter-stage coupling. The differential input voltage range equals the full supply voltage (±36 V max), and large-signal voltage gain exceeds 50 V/mV - sufficient for clean digital transitions with >100 mV overdrive.

Key Specifications

Pinout & Package

LM339D is supplied in SO14 (Small Outline 14-pin) plastic micropackage per JEDEC MS-012, with 1.27 mm pitch, body size 8.75 × 4.0 mm, and thermal resistance R_θJA = 105 °C/W.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar quad voltage comparator applications.

Compared with TL339CDR and LM2901DT, LM339D offers the best balance of precision (±1 mV offset), industrial-grade temperature range (0°C to +70°C), and legacy footprint compatibility - making it optimal for cost-sensitive industrial controls where design reuse and long-term availability are prioritized.

Availability

LM339D is available at Aetrix Electronics and suitable for voltage monitoring systems, zero-crossing detection, transducer signal conditioning, and crystal-controlled oscillator designs requiring stable component supply across multi-year production cycles.

Supply support for LM339D 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, delivering intelligent power, sensing, and control solutions for automotive, industrial, and consumer markets.

The LM339 series belongs to ST's precision analog comparators product line, engineered for robust performance in industrial control, power management, and sensor interface applications where reliability under wide supply and temperature ranges is essential.

FAQ

Can LM339D operate from a single 3.3 V supply?

Yes. LM339D supports single-supply operation from +2 V to +36 V. At 3.3 V, its input common-mode range extends from 0 V to 1.8 V, and output saturation voltage remains ≤400 mV at 4 mA sink current - enabling direct interface with 3.3 V logic families when paired with appropriate pull-up resistors.

Does LM339D require external hysteresis for noise immunity?

Yes - LM339D has no internal hysteresis. For noisy input signals (e.g., motor commutation or relay contact bounce), external positive feedback (e.g., 1 MΩ from output to non-inverting input) must be added to create 10–100 mV of hysteresis, preventing multiple toggles near threshold.

What is the maximum sink current per output of LM339D?

The absolute maximum sink current is 20 mA, but the recommended continuous operating limit is 6 mA per output (per datasheet Table 3, ISINK = 6 mA min at VO = 1.5 V). Exceeding 6 mA risks exceeding junction temperature limits under sustained load without heatsinking.

Is LM339D pin-compatible with LM339N (DIP-14)?

No. LM339D uses SO14 surface-mount packaging with 1.27 mm pitch and gull-wing leads; LM339N uses through-hole DIP-14 with 2.54 mm pitch and straight leads. While functional and electrical characteristics match, mechanical mounting, PCB layout, and reflow/soldering processes differ entirely.