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Texas Instruments LM139AJ
- Part No.:
- LM139AJ
- Manufacturer:
- Texas Instruments
- Category:
- Comparators
- Package:
- 14-CDIP (0.300", 7.62mm)
- Datasheet:
-
LM139AJ.pdf
- Description:
- QUAD DIFFERENTIAL COMPARATOR 14-
- Quantity:
- Payment:
- Shipping:
Inventory:2,849
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Product details
Overview
LM139AJ from Texas Instruments is a quad differential comparator IC designed for precision voltage comparison in wide-supply industrial and military systems. It operates from 2V to 30V, delivers ±9mV max input offset voltage (25°C), supports –55°C to +125°C temperature range, and features open-collector outputs compatible with TTL/MOS/CMOS logic - used in motor drive fault detection and high-reliability power supply monitoring.
For engineers reviewing the LM139AJ datasheet, LM139AJ pinout, LM139AJ application, or LM139AJ equivalent, this page provides verified electrical specs, package mapping to 14-pin PDIP, functional pin roles, real-world use cases in safety-critical analog monitoring, and two validated alternative comparators with documented parametric differences.
Technical Context
The LM139AJ implements four independent voltage comparators on a single silicon die, each with rail-to-rail common-mode input range down to ground and differential input capability up to ±30V. Its open-collector output stage allows wired-OR configuration and flexible pull-up voltage selection independent of VCC.
It uses bipolar transistor technology optimized for stability across extreme temperatures and supply voltages, with internal ESD protection rated at ±2000V HBM. Input bias current remains below –300nA over full temperature range, enabling high-impedance sensor interface without significant loading error.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Supply Voltage Range | 2V to 30V - supports direct operation from unregulated industrial rails or battery-backed systems without LDO pre-regulation. |
| Input Offset Voltage (max) | ±9mV at 25°C - enables accurate threshold detection within ~0.3% of full-scale reference voltage. |
| Input Bias Current (max) | –300nA at –55°C to +125°C - preserves signal integrity when interfacing with high-Z sources like thermistors or photodiodes. |
| Response Time (typ) | 1.3µs - sufficient for overvoltage/undervoltage lockout in switch-mode power supplies with <100kHz switching. |
| Output Type | Open-collector - permits level-shifting, wired-OR logic, and direct interface to 3.3V/5V/12V digital control buses. |
| Operating Temperature | –55°C to +125°C - qualified for aerospace, defense, and under-hood automotive applications per MIL-PRF-38535 Class B. |
| ESD Rating (HBM) | ±2000V - meets standard handling requirements for production environments without special ESD controls. |
Pinout & Package
LM139AJ is supplied in a 14-pin plastic dual in-line package (PDIP) with body size 19.30mm × 6.40mm, suitable for through-hole mounting and legacy PCB designs requiring mechanical robustness and thermal mass.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | OUT1 | Open-collector output of comparator 1 - requires external pull-up resistor to define logic-high voltage level. |
| 2 | IN1− | Inverting input of comparator 1 - accepts signals down to ground; differential range extends to ±30V. |
| 3 | IN1+ | Non-inverting input of comparator 1 - same voltage range and impedance as IN1−. |
| 4 | VCC | Positive supply pin - powers all four comparators; no internal regulation required. |
| 5 | OUT2 | Open-collector output of comparator 2 - electrically isolated from OUT1; supports independent pull-up networks. |
| 6 | IN2− | Inverting input of comparator 2 - shares same electrical characteristics as IN1−. |
| 7 | IN2+ | Non-inverting input of comparator 2 - identical specification to IN1+. |
| 8 | GND | Ground reference for all comparators - must be low-impedance connection to minimize noise coupling. |
| 9 | IN3+ | Non-inverting input of comparator 3 - part of fully independent third comparator channel. |
| 10 | IN3− | Inverting input of comparator 3 - supports common-mode input down to GND. |
| 11 | OUT3 | Open-collector output of comparator 3 - usable for redundant sensing or multi-threshold logic. |
| 12 | IN4+ | Non-inverting input of comparator 4 - completes quad-channel set with matched performance. |
| 13 | IN4− | Inverting input of comparator 4 - maintains same offset and bias specs as other inputs. |
| 14 | OUT4 | Open-collector output of comparator 4 - enables independent status signaling or fault bus aggregation. |
Key Features
| Feature | Design Value |
|---|---|
| Rail-to-rail common-mode input range | Includes ground and extends to VCC − 2V - enables direct sensing of 0V-referenced signals like current shunts or battery terminals. |
| Open-collector outputs | Supports mixed-voltage system interfacing (e.g., 3.3V logic controlling 24V loads) via external pull-up selection. |
| Wide supply voltage range (2V–30V) | Eliminates need for auxiliary regulators in multi-rail systems - simplifies BOM and improves power efficiency. |
| –55°C to +125°C operating range | Qualified for military/aerospace platforms where extended thermal cycling and long-term reliability are mandatory. |
| ±2000V HBM ESD rating | Reduces risk of field failure during handling or deployment in non-ESD-controlled environments. |
Applications
| Motor Drive Protection | Industrial Power Supply Monitoring |
|---|---|
Use Scenario: Real-time overcurrent detection in three-phase inverter gate drivers using shunt resistors. IC Role / Device Role / Timing Role: Quad comparator monitors voltage across each phase shunt; triggers immediate shutdown via OR'd outputs when any exceeds threshold. Use Value: Enables sub-microsecond response to short-circuit events, preventing IGBT destruction before protection firmware intervenes. | Use Scenario: Redundant undervoltage and overvoltage lockout in 48V telecom rectifiers. IC Role / Device Role / Timing Role: Two comparators supervise input AC-derived DC bus; two monitor regulated 12V/5V outputs with hysteresis. Use Value: Provides hardware-level fail-safe cutoff independent of microcontroller, meeting IEC 62368-1 fault tolerance requirements. |
| Aerospace Avionics Sensing | Military Vehicle Battery Management |
Use Scenario: Monitoring multiple 28V aircraft bus voltages and temperature sensor thresholds in flight control units. IC Role / Device Role / Timing Role: LM139AJ compares analog sensor outputs against precision references; outputs feed discrete logic or FPGA interrupt lines. Use Value: Meets DO-160E Section 22 lightning-induced transient immunity due to robust input structure and wide common-mode range. | Use Scenario: State-of-charge estimation and deep-discharge prevention in 24V lead-acid battery banks for armored vehicles. IC Role / Device Role / Timing Role: Four comparators track individual cell voltages and pack temperature gradients using thermistor dividers. Use Value: Sustains operation at –55°C ambient, ensuring cold-start capability in arctic deployments without heater dependency. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar quad differential comparator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LM339N | 0°C to +70°C temp range; ±9mV offset (same); 2V–30V supply; PDIP-14 package. | Limited to commercial-grade systems; not qualified for extended temperature or military use. | Select when cost sensitivity outweighs environmental ruggedness and full-specification compliance is unnecessary. |
| LM2901DT | –40°C to +125°C range; ±7mV offset (improved); SOIC-14 package; 2V–36V supply. | Suitable for modern surface-mount industrial controllers but lacks MIL-PRF-38535 qualification. | Choose for higher-precision, space-constrained designs where extended voltage range and smaller footprint are priorities. |
Compared with LM139AJ, LM339N sacrifices temperature range and qualification for lower cost, while LM2901DT offers better offset and wider supply range in a compact SOIC package - neither matches LM139AJ's –55°C capability or military pedigree.
Availability
LM139AJ is available at Aetrix Electronics and suitable for motor drive protection, aerospace avionics sensing, and military vehicle battery management requiring stable component supply across extended temperature extremes and long product lifecycles.
Supply support for LM139AJ 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
Texas Instruments is a global semiconductor leader delivering analog and embedded processing solutions for industrial, automotive, and aerospace markets.
The LM139 family was engineered for high-reliability analog monitoring in mission-critical systems, emphasizing wide temperature operation, input ruggedness, and compatibility with legacy military and industrial designs.
FAQ
What is the maximum supply voltage rating for LM139AJ?
The LM139AJ has an absolute maximum supply voltage of 36V, but its recommended operating range is 2V to 30V. Operation above 30V risks exceeding specified electrical characteristics such as input offset drift and propagation delay; TI specifies 30V as the upper limit for guaranteed performance across the full –55°C to +125°C temperature range. Always observe derating guidelines in MIL-PRF-38535 for sustained reliability.
Does LM139AJ support rail-to-rail input operation?
Yes, the LM139AJ supports rail-to-rail common-mode input voltage from ground (V–) up to VCC – 2V. Either input can go to VCC without damage, and proper output states are maintained as long as at least one input stays within the valid common-mode range. This enables direct interface with sensors referenced to ground or VCC, such as current-sense amplifiers or resistive divider networks.
What is the typical response time of LM139AJ?
The LM139AJ exhibits a typical response time of 1.3µs under standard test conditions (100mV input step, 5mV overdrive, RL = 5.1kΩ to 5V, CL = 15pF). This value holds across the full operating temperature range and supply voltage (2V–30V), making it suitable for fast fault detection in power electronics where reaction times under 2µs are required to prevent device failure.
Can LM139AJ outputs be wire-OR'd together?
Yes, all four outputs of the LM139AJ are open-collector and can be safely connected to a shared pull-up resistor - enabling wired-OR logic for aggregated fault signaling. This configuration is commonly used to combine overtemperature, overcurrent, and overvoltage alerts into a single system interrupt line without additional logic gates or level translators.
Is LM139AJ pin-compatible with other LM339-series comparators?
Yes, the LM139AJ shares identical pinout and electrical behavior with LM339, LM239, LM2901, and their 'A' variants in the same PDIP-14 package. Functional equivalence is confirmed by TI's family comparison table and drop-in replacement guidance; however, temperature range, offset voltage, and ESD rating differ between grades - verify datasheet sections 6.9 and 6.10 for exact parameter alignment before substitution.
LM139AJ Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Package/Case:
- 14-CDIP (0.300", 7.62mm)
- Series:
- -
- Packaging:
- Tube
- Product Status:
- Active
- Type:
- General Purpose
- Number of Elements:
- 4
- Output Type:
- Open-Collector, Open-Drain
- Voltage - Supply, Single/Dual (±):
- 5V ~ 30V, ±2.5V ~ 15V
- :
- 2mV @ 30V
- Voltage - Input Offset (Max):
- 0.1µA @ 5V
- Current - Input Bias (Max):
- 20mA
- Current - Output (Typ):
- 2mA
- Current - Quiescent (Max):
- 70dB CMRR, 70dB PSRR
- CMRR, PSRR (Typ):
- 1.3µs (Typ)
- Propagation Delay (Max):
- 10mV
- Hysteresis:
- -55°C ~ 125°C
- Operating Temperature:
- -
- Grade:
- -
- Qualification:
- Through Hole
- :
- 14-CDIP
LM139AJ FAQ
1.How can I place an order for LM139AJ through Aetrix?
Please submit a Request for Quotation (RFQ) for LM139AJ 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 LM139AJ reliable?
The price and inventory of LM139AJ are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LM139AJ is usually 5 days.
3.What payment methods are accepted for LM139AJ?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LM139AJ transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LM139AJ?
LM139AJ orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LM139AJ 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 LM139AJ?
For technical support, including LM139AJ datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LM139AJ requirements.
6.How does Aetrix verify that LM139AJ is sourced from the original manufacturer or authorized distributors?
All LM139AJ 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 LM139AJ meets industry standards.
7.What is the process for return or replacement of LM139AJ?
All LM139AJ units undergo pre-shipment inspection (PSI). If there is an issue with LM139AJ, 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 LM139AJ part is unused and in its original packaging.
Return procedure for LM139AJ:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LM139AJ Tags
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