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Home > Products > Integrated Circuits (ICs) > Linear > Comparators

STMicroelectronics LM239AN

Name: LM239AN
Brand: STMicroelectronics
SKU: LM239AN
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: LM239AN

Manufacturer:: STMicroelectronics

Category:: Comparators

Package:: 14-DIP (0.300", 7.62mm)

Datasheet:: LM239AN.pdf

Description:: IC COMPARATOR 4 GEN PUR 14DIP

Quantity:: RFQ Add To RFQ list

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Inventory:4,432

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Product details

Overview

LM239AN from STMicroelectronics is a low-power quad voltage comparator designed for single-supply operation (2–36 V) or dual supplies (±1 V to ±18 V), featuring 1.1 mA supply current, ±1 mV typical input offset voltage, 25 nA typical input bias current, and rail-to-rail input common-mode range including ground. It drives TTL/CMOS loads with 250 mV typical output saturation voltage at 4 mA sink current and is used in voltage monitoring, window detection, and analog-to-digital interface circuits.

For engineers reviewing the LM239AN datasheet, LM239AN pinout, LM239AN application, or LM239AN equivalent, key selection criteria include input offset voltage stability over temperature, output sink capability under varying supply conditions, compatibility with legacy DIP-14 footprints, and suitability for industrial sensor signal conditioning where ground-referenced inputs are required.

Technical Context

The LM239AN implements four independent open-collector comparators with PNP input stages enabling input voltages down to ground on single-supply operation. Its differential input voltage range equals the full supply voltage (±36 V max), and input bias current flows *out* of both inputs-enabling high-impedance reference networks without loading error.

Output stage design supports direct interfacing to TTL, DTL, ECL, MOS, and CMOS logic families via external pull-up; no internal level-shifting or push-pull drivers are included. Thermal resistance (R_thJA) is 105 °C/W in SO14 package, with junction temperature rated to +150 °C and storage range from –65 °C to +150 °C.

Key Specifications

Parameter	Value and Actual Design Meaning
Supply Voltage Range	+2 V to +36 V (single) or ±1 V to ±18 V (dual) - supports wide industrial input rails without regulation
Input Offset Voltage	±1 mV typ - enables accurate threshold detection within 1 mV at room temperature
Supply Current	1.1 mA typ (all four comparators) - stable across supply voltage, minimizing power budget impact
Input Bias Current	25 nA typ - permits use with megaohm-level resistor dividers without significant error
Output Saturation Voltage	250 mV typ at 4 mA sink - ensures reliable low-state logic recognition with standard pull-ups
Response Time	1.3 μs (100 mV step, 5 mV overdrive) - suitable for sub-1 MHz threshold detection in control loops
Common-Mode Input Range	0 V to (V_CC+ − 1.5 V) - includes ground on single supply, eliminating need for level shifters

Pinout & Package

LM239AN is supplied in a 14-pin plastic DIP (Dual In-line Package) with through-hole mounting. Pin assignments follow industry-standard quad comparator layout optimized for PCB layout efficiency and noise immunity in mixed-signal systems.

Pin/Terminal	Circuit Role	Design Meaning
1	Output 1	Open-collector output requiring external pull-up; sinks up to 16 mA
2	Inverting Input 1	PNP-based input; bias current flows out, enabling high-Z references
3	Non-inverting Input 1	Same PNP structure as Pin 2; common-mode range includes ground
4	GND / V_CC−	Ground reference or negative supply rail; all inputs referenced to this node
5	Non-inverting Input 2	Independent comparator input; electrically isolated from other sections
6	Inverting Input 2	Matches Pin 2 characteristics; supports differential or single-ended sensing
7	Output 2	Open-collector; identical sink behavior to Pin 1
8	V_CC+	Positive supply rail; powers all four comparators; decoupling recommended
9	Output 3	Third open-collector output; shares V_CC+ and GND with others
10	Inverting Input 3	Third comparator input; no crosstalk with other sections per datasheet testing
11	Non-inverting Input 3	Paired with Pin 10; supports independent threshold comparison
12	Non-inverting Input 4	Fourth comparator input; fully functional across full temperature range
13	Inverting Input 4	Final input pair; validated for operation at T_A = –40 °C to +105 °C
14	Output 4	Fourth open-collector output; matches electrical specs of Pins 1, 7, and 9

Key Features

Feature	Design Value
Single-supply operation with ground-sensing inputs	Enables direct interface to 0 V-referenced sensors (e.g., thermistors, RTDs) without level-shifting circuitry
Low quiescent current (1.1 mA)	Reduces thermal load and extends battery life in portable industrial monitors
Input offset voltage ≤ 2 mV (max)	Supports precise window-comparator designs for ±10 mV fault detection thresholds
Output compatible with TTL/CMOS/MOS logic	Eliminates need for buffer ICs when driving microcontroller GPIO or FPGA inputs
Differential input voltage = supply voltage	Allows one input to swing beyond V_CC+ (e.g., 30 V input on 5 V system) while maintaining valid output

Applications

Voltage Monitoring System

Window Comparator Circuit

Use Scenario: Monitoring 24 V DC power rail in PLC backplane for undervoltage/overvoltage faults.

IC Role / Device Role / Timing Role: Quad comparator configured as two independent high/low threshold detectors with hysteresis.

Use Value: Detects deviations >±2% from nominal using internal precision offsets and stable sink current to drive LED indicators or MCU interrupt lines.

Use Scenario: Detecting if motor current stays within safe operating bounds during startup surge.

IC Role / Device Role / Timing Role: Two comparators compare sensed current against upper/lower reference voltages; third generates enable signal.

Use Value: Prevents false trips during transient inrush by leveraging 1.3 μs response time and rail-to-rail input range covering 0–5 V sense signal.

Zero-Crossing Detector

Transducer Signal Conditioning

Use Scenario: Isolating AC line zero-cross events for phase-controlled dimmer in smart lighting.

IC Role / Device Role / Timing Role: Single comparator compares rectified AC waveform to ground reference with Schmitt-trigger hysteresis added externally.

Use Value: Achieves <10 μs timing jitter due to low input capacitance and consistent 250 mV saturation voltage across temperature.

Use Scenario: Amplifying low-level magnetic pickup signals (e.g., crankshaft position) in engine control units.

IC Role / Device Role / Timing Role: Comparator converts analog sine wave into clean digital edge for timing-critical ignition sequencing.

Use Value: PNP input stage draws only 25 nA, preserving signal integrity from high-impedance 20 MΩ transducer source.

Equivalent & Alternatives

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

Alternative Part	Technical Difference	Application Difference	Selection Advice
LM339N	Wider operating temperature range (0 °C to +70 °C vs. –40 °C to +105 °C); same electrical specs and pinout	Suitable for commercial-grade equipment; not qualified for extended industrial environments	Select LM339N only when ambient temperature remains within 0–70 °C and cost is primary driver
TLV339IPW	Lower supply current (12 μA), rail-to-rail inputs/outputs, but limited supply range (1.8–5.5 V) and SMT-only TSSOP-14 package	Targets ultra-low-power battery systems; incompatible with 12/24 V industrial rails	Choose TLV339IPW only for 3.3 V embedded systems requiring nanoamp quiescent current and surface-mount assembly

Compared with LM339N, LM239AN offers extended temperature qualification critical for factory automation; versus TLV339IPW, it supports higher supply voltages and through-hole assembly but consumes ~90× more current-making LM239AN optimal for robust, mains-powered industrial signal conditioning where legacy DIP footprint matters.

Availability

LM239AN is available at Aetrix Electronics and suitable for voltage monitoring systems, window comparator circuits, zero-crossing detectors, and transducer signal conditioning requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for LM239AN 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, designing and manufacturing analog, microcontroller, power, and sensor solutions for industrial, automotive, and consumer markets.

The LM239 series belongs to ST's precision analog comparators product line, engineered specifically for industrial control, power management, and sensor interface applications demanding reliability across wide temperature and supply ranges.

FAQ

Can LM239AN operate from a single 3.3 V supply?

No. The LM239AN minimum single-supply voltage is +2 V, but its input common-mode range requires at least 1.5 V headroom below V_CC+, limiting usable input range to 0–1.8 V at 3.3 V supply. For 3.3 V systems, rail-to-rail input comparators like TLV339 are recommended instead.

Does LM239AN have internal hysteresis?

No. The LM239AN has no internal hysteresis. External positive feedback must be added to implement hysteresis for noise immunity in slow-moving or noisy input signals-typical values use 1–10 MΩ resistors between output and non-inverting input.

What is the maximum sink current per output?

The LM239AN outputs are rated for 16 mA sink current (I_SINK) under specified conditions (V_ID = 1 V, V_O = 1.5 V). Absolute maximum ratings allow indefinite short-circuit to ground, but thermal limits constrain continuous operation-derate above 6 mA at elevated ambient temperatures.

Is LM239AN RoHS compliant and lead-free?

Yes. LM239AN is manufactured in ST's ECOPACK®-compliant DIP-14 package, meeting RoHS Directive 2011/65/EU and REACH regulations. Lead content is below 0.1 wt%, and the device carries the "ECOPACK2" marking per ST's environmental compliance documentation.

LM239AN Specifications

Product attributes: Attribute value

Manufacturer:: STMicroelectronics

Package/Case:: 14-DIP (0.300", 7.62mm)

Series:: -

Packaging:: Tube

Product Status:: Obsolete

Type:: General Purpose

Number of Elements:: 4

Output Type:: CMOS, DTL, ECL, MOS, Open-Collector, TTL

Voltage - Supply, Single/Dual (±):: 2V ~ 32V, ±1V ~ 16V

:: 2mV @ 30V

Voltage - Input Offset (Max):: 0.1µA @ 5V

Current - Input Bias (Max):: 16mA @ 5V

Current - Output (Typ):: 2mA

Current - Quiescent (Max):: -

CMRR, PSRR (Typ):: -

Propagation Delay (Max):: -

Hysteresis:: -40°C ~ 105°C

Operating Temperature:: -

Grade:: -

Qualification:: Through Hole

:: 14-DIP

LM239AN FAQ

1.How can I place an order for LM239AN through Aetrix?

Please submit a Request for Quotation (RFQ) for LM239AN on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.

2.Are the price and stock information for LM239AN reliable?

The price and inventory of LM239AN are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LM239AN is usually 5 days.

3.What payment methods are accepted for LM239AN?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LM239AN transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for LM239AN?

LM239AN orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your LM239AN order is processed, you will receive an email with the shipment details and tracking number.

Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.

5.How can I obtain technical support or documentation for LM239AN?

For technical support, including LM239AN datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LM239AN requirements.

6.How does Aetrix verify that LM239AN is sourced from the original manufacturer or authorized distributors?

All LM239AN products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that LM239AN meets industry standards.

7.What is the process for return or replacement of LM239AN?

All LM239AN units undergo pre-shipment inspection (PSI). If there is an issue with LM239AN, returns or replacements are accepted under the following conditions:

1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.

2.The issue is reported within 90 days of delivery.

3.The LM239AN part is unused and in its original packaging.

Return procedure for LM239AN:

1.Submit a request within 90 days.

2.Obtain a Return Material Authorization (RMA) from Aetrix.

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