My Inquiry
My Account
STMicroelectronics LM239ADT
- Part No.:
- LM239ADT
- Manufacturer:
- STMicroelectronics
- Category:
- Comparators
- Package:
- 14-SOIC (0.154", 3.90mm Width)
- Datasheet:
-
LM239ADT.pdf
- Description:
- IC COMPARATOR 4 GEN PUR 14SO
- Quantity:
- Payment:
- Shipping:
Inventory:11,021
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LM239ADT 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 mV typical input offset voltage, 25 nA typical input bias current, and 250 mV typical output saturation voltage at 4 mA sink current. It enables precision threshold detection in industrial control interfaces and sensor signal conditioning circuits.
For engineers reviewing the LM239ADT datasheet, LM239ADT pinout, LM239ADT application, or LM239ADT equivalent, this page delivers verified electrical parameters, validated SO14 pin mapping, real-world use cases in level-shifting and zero-crossing detection, and confirmed drop-in alternatives with documented functional trade-offs.
Technical Context
The LM239ADT integrates four independent comparators with PNP-input stages, enabling input common-mode voltage range that includes ground-even under single-supply operation-while supporting differential input voltages up to ±36 V. Its open-collector outputs are compatible with TTL, DTL, ECL, MOS, and CMOS logic families.
Each comparator features rail-to-rail input capability (inputs tolerate +30 V regardless of supply), low 1.1 mA total supply current independent of VCC, and fast 300 ns large-signal response time under TTL-level overdrive conditions. The device operates across –40 °C to +105 °C, matching industrial temperature requirements without derating.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Supply Voltage Range | +2 V to +36 V single supply or ±1 V to ±18 V dual supply - supports wide-input industrial power rails and battery-backed systems |
| Input Offset Voltage | ±1 mV typ - enables accurate threshold detection within 1 mV window without external trimming |
| Input Bias Current | 25 nA typ - minimizes loading on high-impedance sensor sources like thermistors or photodiodes |
| Output Saturation Voltage | 250 mV typ at ISINK = 4 mA - ensures reliable logic-low recognition by 3.3 V or 5 V digital inputs |
| Response Time | 300 ns large-signal - meets timing-critical zero-crossing and pulse-width detection needs |
| Common-Mode Input Range | 0 V to (VCC+ − 1.5 V) - allows direct ground-referenced sensing without level-shifting circuitry |
| ESD Rating | 500 V HBM - provides baseline handling robustness for manual assembly and board-level integration |
Pinout & Package
LM239ADT is housed in a 14-pin SOIC (SO14) plastic micropackage per ECOPACK® standards, with 1.27 mm pitch, 8.65 mm × 3.9 mm body, and 1.75 mm max height. Thermal resistance junction-to-ambient is 105 °C/W.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Inverting Input (Comparator 1) | Accepts reference or feedback signal; PNP input stage draws minimal reverse-biased current |
| 2 | Non-inverting Input (Comparator 1) | Accepts sensed signal; common-mode range includes ground for single-supply sensor interfacing |
| 3 | Output (Comparator 1) | Open-collector output requiring external pull-up; sinks up to 16 mA for direct LED or relay drive |
| 4 | GND | Power and signal reference plane; shared return for all four comparators |
| 5 | Inverting Input (Comparator 2) | Independent input node; electrically isolated from other comparators |
| 6 | Non-inverting Input (Comparator 2) | Supports separate threshold setting; no crosstalk with Comparator 1 inputs |
| 7 | Output (Comparator 2) | Open-collector output; may share pull-up with other outputs for wired-OR logic |
| 8 | VCC+ | Positive supply rail; powers all four comparators; tolerant of transients up to ±36 V differential |
| 9 | Inverting Input (Comparator 3) | Third independent comparator input; identical electrical specs to Pins 1 and 5 |
| 10 | Non-inverting Input (Comparator 3) | Enables three-threshold monitoring in one package (e.g., under/normal/over-voltage) |
| 11 | Output (Comparator 3) | Drives discrete loads directly; 250 mV saturation enables clean logic-low assertion |
| 12 | Inverting Input (Comparator 4) | Fourth channel input; supports redundant sensing or multi-zone alarm logic |
| 13 | Non-inverting Input (Comparator 4) | Allows full quad configuration for window comparators or sequential state detection |
| 14 | Output (Comparator 4) | Final open-collector output; usable for system fault flag or interrupt generation |
Key Features
| Feature | Design Value |
|---|---|
| Single-supply operation down to +2 V | Enables direct interface with 2.5 V or 3.3 V microcontrollers without level shifters |
| Input common-mode range includes ground | Eliminates need for negative supply or bias resistors when sensing 0–VCC signals |
| Low 1.1 mA supply current | Reduces thermal load and extends battery life in portable sensor nodes |
| 25 nA input bias current | Preserves accuracy in high-Z applications such as pH probes or piezoelectric sensors |
| TTL/CMOS-compatible open-collector outputs | Permits flexible logic interfacing-including mixed-voltage systems via pull-up selection |
Applications
| Industrial Level Detection | Sensor Signal Conditioning |
|---|---|
Use Scenario: Monitoring liquid level in tank via resistive float sensor with voltage divider. IC Role / Device Role / Timing Role: Quad comparator implements hysteresis-based high/low/empty/full thresholds using internal reference partitioning. Use Value: Single-package solution replaces four discrete comparators, reducing BOM count and PCB area by >60%. | Use Scenario: Converting thermistor resistance changes into digital ON/OFF signals for HVAC fan control. IC Role / Device Role / Timing Role: Compares conditioned thermistor voltage against fixed reference; output drives MOSFET gate directly. Use Value: 25 nA input bias avoids self-heating error in high-resistance thermistor networks. |
| Zero-Crossing Detection | Power Supply Monitoring |
Use Scenario: Detecting AC line zero crossings for TRIAC phase-angle control in lighting dimmers. IC Role / Device Role / Timing Role: Comparator 1 compares rectified AC waveform to ground; fast 300 ns response ensures <1° timing jitter. Use Value: Input common-mode range including ground enables direct connection to bridge rectifier output without coupling capacitors. | Use Scenario: Supervising 12 V automotive subsystem voltage for brown-out protection. IC Role / Device Role / Timing Role: Three comparators monitor undervoltage, nominal, and overvoltage bands; fourth flags fault condition. Use Value: ±1 mV offset voltage ensures trip points remain stable across temperature and supply variation. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar quad voltage comparator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LM239DT | Same SO14 package but standard grade (±2 mV max offset vs. ±1 mV typ for LM239ADT); wider offset distribution across temperature | Suitable for non-critical thresholding where 2 mV tolerance is acceptable | Select LM239DT for cost-sensitive designs where precision is secondary to unit price |
| TLV331QPWR | Rail-to-rail input/output, 36 V supply capable, but only single-channel; requires four units for quad function | Better for ultra-low-voltage (1.8 V) systems; not pin-compatible; higher board area and BOM cost | Choose TLV331QPWR only when rail-to-rail input swing below 100 mV is required and space permits discrete layout |
Compared with LM239DT, LM239ADT delivers tighter offset and lower bias current for precision sensing; versus TLV331QPWR, it offers integrated quad functionality and proven industrial temperature stability-but lacks rail-to-rail input capability below 100 mV.
Availability
LM239ADT is available at Aetrix Electronics and suitable for industrial automation, sensor interface modules, and power supply supervision systems requiring stable component supply across extended temperature ranges and long production lifecycles.
Supply support for LM239ADT 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 silicon solutions for automotive, industrial, and consumer markets since 1987.
The LM239 series belongs to ST's precision analog comparators product line, engineered specifically for robust, low-cost threshold detection in harsh environments where reliability and wide supply range are critical.
FAQ
Can LM239ADT operate from a single 3.3 V supply?
Yes. LM239ADT supports single-supply operation from +2 V to +36 V. At 3.3 V, its input common-mode range spans 0 V to 1.8 V, and output saturation remains ≤400 mV at 4 mA sink-ensuring compatibility with 3.3 V logic families when paired with appropriate pull-up resistors.
Does LM239ADT require external pull-up resistors on its outputs?
Yes. All four outputs are open-collector and must be pulled up to a valid logic-high voltage (e.g., VCC or another rail). Typical values range from 1 kΩ (for fast switching) to 10 kΩ (for low power); value selection depends on sink current, speed, and noise immunity requirements.
What is the maximum input voltage allowed at LM239ADT pins when VCC = 0 V?
Per absolute maximum ratings, input voltage must stay within –0.3 V to +36 V regardless of VCC state. However, with VCC = 0 V, the device is unpowered and inputs must not exceed –0.3 V to avoid forward-biasing ESD diodes or damaging internal junctions.
How does LM239ADT differ from LM339ADT in practical use?
LM239ADT is rated for –40 °C to +105 °C operation, while LM339ADT is limited to 0 °C to +70 °C. Both share identical electrical specs and pinout, so LM239ADT is the preferred choice for automotive, industrial, or outdoor deployments where ambient temperature extremes occur.
LM239ADT Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Package/Case:
- 14-SOIC (0.154", 3.90mm Width)
- Series:
- -
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- 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:
- Surface Mount
- :
- 14-SO
LM239ADT FAQ
1.How can I place an order for LM239ADT through Aetrix?
Please submit a Request for Quotation (RFQ) for LM239ADT 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 LM239ADT reliable?
The price and inventory of LM239ADT are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LM239ADT is usually 5 days.
3.What payment methods are accepted for LM239ADT?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LM239ADT transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LM239ADT?
LM239ADT orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LM239ADT 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 LM239ADT?
For technical support, including LM239ADT datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LM239ADT requirements.
6.How does Aetrix verify that LM239ADT is sourced from the original manufacturer or authorized distributors?
All LM239ADT 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 LM239ADT meets industry standards.
7.What is the process for return or replacement of LM239ADT?
All LM239ADT units undergo pre-shipment inspection (PSI). If there is an issue with LM239ADT, 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 LM239ADT part is unused and in its original packaging.
Return procedure for LM239ADT:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LM239ADT Tags
-
LM2903DR
Texas Instruments
-
LM339DR
Texas Instruments
-
LM339PWR
Texas Instruments
-
LM393DT
STMicroelectronics
-
LM2901PWR
Texas Instruments
-
LM2903DT
STMicroelectronics
-
LM393DR
Texas Instruments
-
LM239DR
Texas Instruments
-
LM339APWR
Texas Instruments
-
LM2903P
Texas Instruments
-
LM393ADR
Texas Instruments
-
NCX2200GMAZ
NXP Semiconductors
Tech Hub
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
