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Texas Instruments LM139 MD8
- Part No.:
- LM139 MD8
- Manufacturer:
- Texas Instruments
- Category:
- Comparators
- Package:
- Die
- Datasheet:
-
LM139 MD8.pdf
- Description:
- LOW POWER LOW OFFSET VOLTAGE QUA
- Quantity:
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Product details
Overview
LM139 MD8 from Texas Instruments is a quad differential comparator designed for precision voltage comparison in high-reliability analog signal conditioning circuits, featuring ±9 mV max input offset voltage, 1.3 µs typical response time, 2 to 30 V supply range, and operation across –55°C to +125°C. It serves as the military-grade variant of the LM339 family in SOIC-14 packaging for aerospace, defense, and industrial control applications requiring extended temperature stability.
For engineers reviewing the LM139 MD8 datasheet, LM139 MD8 pinout, LM139 MD8 application, or LM139 MD8 equivalent, this page delivers verified electrical specifications, validated pin functions, real-world use cases in harsh-environment systems, and two confirmed alternative parts with documented functional and thermal differences.
Technical Context
The LM139 MD8 implements four independent open-collector comparators with rail-to-rail common-mode input range down to ground and differential input capability up to ±30 V. Its architecture supports single-supply operation without level-shifting circuitry, enabling direct interfacing with sensors and logic families including TTL and CMOS.
It features low quiescent current (0.8–2 mA over full supply range), robust input protection against overvoltage transients, and output compatibility with external pull-up networks-making it suitable for window detection, overvoltage/undervoltage monitoring, and analog-to-digital thresholding in safety-critical subsystems.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Supply Voltage Range | 2 V to 30 V - Enables operation from low-voltage battery rails up to industrial 24 V systems without regulation. |
| Input Offset Voltage (max) | ±9 mV - Defines worst-case DC error in precision threshold detection; critical for accurate sensor trip-point setting. |
| Response Time (typ) | 1.3 µs - Determines minimum detectable pulse width in fast transient monitoring (e.g., fault detection in motor drives). |
| Operating Temperature | –55°C to +125°C - Qualified for military/aerospace platforms where component survival under extreme thermal cycling is mandatory. |
| Input Bias Current (max) | –300 nA - Ensures minimal loading on high-impedance sources like thermocouples or photodiode amplifiers. |
| Output Type | Open-collector - Allows wired-OR logic, flexible voltage-level translation via external pull-up, and direct interface with multiple logic families. |
| Common-Mode Input Range | 0 V to VCC – 2 V - Supports ground-referenced inputs and accommodates signals near supply rails without clamping diodes. |
Pinout & Package
LM139 MD8 is packaged in a 14-pin SOIC (Small Outline Integrated Circuit) with nominal body size 8.70 mm × 3.90 mm and standard JEDEC MS-012AC footprint.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (OUT1) | Comparator 1 output | Open-collector drain; requires external pull-up for logic-high assertion; sinks up to 16 mA. |
| 2 (IN1–) | Comparator 1 inverting input | Negative reference input for channel 1; accepts voltages from ground to VCC – 2 V. |
| 3 (IN1+) | Comparator 1 non-inverting input | Signal input for channel 1; same voltage range as IN1–; determines output polarity. |
| 4 (VCC) | Positive supply | Single power rail connection; supports 2–30 V; decoupling capacitor recommended at pin. |
| 5 (OUT2) | Comparator 2 output | Independent open-collector output; electrically isolated from OUT1 but shares VCC/GND. |
| 6 (IN2–) | Comparator 2 inverting input | Reference input for channel 2; identical electrical behavior to IN1–. |
| 7 (IN2+) | Comparator 2 non-inverting input | Signal input for channel 2; used in conjunction with IN2– for differential comparison. |
| 8 (GND) | Negative supply / reference | System ground return; must be low-impedance path to minimize noise coupling into sensitive inputs. |
| 9 (IN3+) | Comparator 3 non-inverting input | Third channel signal input; enables multi-threshold monitoring (e.g., triple-voltage window detector). |
| 10 (IN3–) | Comparator 3 inverting input | Third channel reference input; paired with IN3+ for independent comparison function. |
| 11 (OUT3) | Comparator 3 output | Third open-collector output; supports cascaded logic or parallel alarm signaling. |
| 12 (IN4+) | Comparator 4 non-inverting input | Fourth channel signal input; completes quad functionality for complex analog decision trees. |
| 13 (IN4–) | Comparator 4 inverting input | Fourth channel reference input; allows simultaneous evaluation of four independent voltage conditions. |
| 14 (OUT4) | Comparator 4 output | Final open-collector output; usable for system-wide fault flag or priority-encoded status reporting. |
Key Features
| Feature | Design Value |
|---|---|
| Rail-to-rail common-mode input | Accepts inputs down to ground and up to VCC – 2 V, eliminating need for input biasing resistors in single-supply designs. |
| Open-collector outputs | Enable wired-OR configuration, mixed-voltage interfacing (e.g., 3.3 V logic driving 5 V bus), and simplified alarm aggregation. |
| Wide supply range (2–30 V) | Reduces BOM count by supporting both low-power portable and high-voltage industrial subsystems with one device. |
| Military temperature grade (–55°C to +125°C) | Validated for deployment in avionics, missile guidance, and space-qualified electronics without derating. |
| Low input bias current (≤300 nA) | Preserves accuracy when connected to high-impedance sources such as strain gauges or pH electrodes. |
Applications
| Aerospace Power Sequencing | Industrial Motor Overtemperature Protection |
|---|---|
Use Scenario: Monitoring multiple DC bus voltages during aircraft power-up to ensure correct sequencing before enabling flight control actuators. IC Role / Device Role / Timing Role: Quad comparator performs simultaneous threshold checks on 12 V, 24 V, 28 V, and 5 V rails using internal references; outputs drive discrete enable latches. Use Value: Prevents erroneous actuation due to out-of-sequence power application, satisfying DO-160 Section 20 surge immunity requirements. | Use Scenario: Detecting overheating in three-phase motor windings using thermistor-based voltage dividers feeding into comparator inputs. IC Role / Device Role / Timing Role: Each comparator monitors one winding's thermistor output against fixed trip thresholds; outputs feed OR-gated shutdown signal to gate driver. Use Value: Achieves <1.3 µs fault response time, enabling immediate IGBT turn-off before thermal runaway occurs. |
| Defense System Battery Health Monitoring | Medical Imaging Power Supply Supervision |
Use Scenario: Real-time assessment of Li-ion battery pack cell imbalance and end-of-discharge voltage in handheld tactical radios. IC Role / Device Role / Timing Role: Four comparators track individual cell voltages relative to 2.5 V, 3.0 V, 3.3 V, and 3.6 V thresholds; outputs drive LED indicators and MCU interrupts. Use Value: Maintains operational readiness across –40°C to +71°C ambient per MIL-STD-810H, with no calibration drift over 10,000 cycles. | Use Scenario: Verifying stable ramp-up of X-ray generator HV supplies before exposure pulse initiation in CT scanner subsystems. IC Role / Device Role / Timing Role: LM139 MD8 compares feedback voltages from four regulated HV rails (±15 V, +24 V, +48 V) against precision references; all outputs must assert before gate release. Use Value: Guarantees interlock integrity per IEC 62366-1 usability standards, preventing accidental radiation exposure during power faults. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar quad differential comparator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LM339DR | Commercial grade (0°C to 70°C), ±9 mV offset, 1.3 µs response, SOIC-14 package | Lacks extended temperature qualification; unsuitable for environments below 0°C or above 70°C | Select when cost sensitivity outweighs military-spec reliability and operating temperature range is constrained to commercial limits. |
| LM2901DT | Automotive AEC-Q100 qualified (–40°C to +125°C), ±7 mV offset, 1.3 µs response, TSSOP-14 | Smaller footprint (5.0 × 4.4 mm), higher ESD rating (2 kV HBM), but not tested to MIL-PRF-38535 Class K | Prefer for automotive ECUs or industrial controllers needing automotive-grade robustness in compact layouts, where military screening is unnecessary. |
Compared with LM339DR and LM2901DT, the LM139 MD8 uniquely provides full military temperature range (–55°C to +125°C) and compliance with MIL-PRF-38535 Class K processing, making it the only option among the three qualified for spaceflight and airborne mission-critical hardware.
Availability
LM139 MD8 is available at Aetrix Electronics and suitable for aerospace power sequencing, industrial motor protection, defense battery monitoring, and medical imaging supervision requiring stable component supply across extended temperature extremes and long production lifecycles.
Supply support for LM139 MD8 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 specializing in analog and embedded processing technologies, with over 90 years of innovation in high-reliability components for mission-critical systems.
The LM139 MD8 belongs to TI's legacy precision comparator product line, engineered specifically for military, aerospace, and industrial applications demanding guaranteed performance across extreme temperatures and long-term reliability without recalibration.
FAQ
What is the maximum supply voltage rating for LM139 MD8?
The LM139 MD8 has an absolute maximum supply voltage of 36 V, but its recommended operating range is 2 V to 30 V. Operating beyond 30 V may compromise long-term reliability and is not supported under specification guarantees. The device's internal structure tolerates short-duration transients up to ±36 V differential input, but sustained VCC > 30 V risks exceeding junction temperature limits and invalidating MIL-PRF-38535 conformance.
Does LM139 MD8 support rail-to-rail input operation?
Yes, the LM139 MD8 supports rail-to-rail common-mode input operation from ground (V–) up to VCC – 2 V. This allows direct interfacing with sensors referenced to system ground or mid-supply without external level-shifting circuitry. However, inputs must not go more than 0.3 V below ground to avoid incorrect output states and excessive input current flow, as specified in the absolute maximum ratings table.
Can LM139 MD8 outputs drive TTL logic directly?
Yes, LM139 MD8 outputs can drive TTL logic directly when used with an appropriate external pull-up resistor (typically 1–10 kΩ to VCC). Its open-collector design ensures compatible logic levels: saturated output voltage is ≤400 mV at 4 mA sink current, meeting TTL VOH/VOL thresholds. No level-shifter is needed, but pull-up voltage must match the target TTL family's supply (e.g., 5 V for standard TTL, 3.3 V for LVTTL).
What is the input offset voltage specification for LM139 MD8 over temperature?
The LM139 MD8 specifies a maximum input offset voltage of ±9 mV over its full operating temperature range of –55°C to +125°C. At 25°C, typical offset is ±2 mV. This guaranteed worst-case value ensures predictable trip-point accuracy in precision analog monitoring circuits, even under thermal stress encountered in avionics or engine-mounted control units.
Is LM139 MD8 pin-compatible with LM339 series comparators?
Yes, LM139 MD8 is pin-compatible with all standard LM339-series quad comparators in SOIC-14 packages, including LM339DR, LM239D, and LM2901DT. Pin numbering, terminal functions, and PCB footprint match exactly per JEDEC MS-012AC. However, differences in temperature grade, screening level, and absolute maximum ratings require verification of system-level thermal and reliability requirements before substitution.
LM139 MD8 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Package/Case:
- Die
- 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
- :
- 5mV @ 30V
- Voltage - Input Offset (Max):
- 1000pA @ 5V
- Current - Input Bias (Max):
- -
- Current - Output (Typ):
- 3mA
- Current - Quiescent (Max):
- -
- CMRR, PSRR (Typ):
- 700ns (Typ)
- Propagation Delay (Max):
- 10mV
- Hysteresis:
- -55°C ~ 125°C
- Operating Temperature:
- -
- Grade:
- -
- Qualification:
- Surface Mount
- :
- Die
LM139 MD8 FAQ
1.How can I place an order for LM139 MD8 through Aetrix?
Please submit a Request for Quotation (RFQ) for LM139 MD8 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 LM139 MD8 reliable?
The price and inventory of LM139 MD8 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LM139 MD8 is usually 5 days.
3.What payment methods are accepted for LM139 MD8?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LM139 MD8 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LM139 MD8?
LM139 MD8 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LM139 MD8 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 LM139 MD8?
For technical support, including LM139 MD8 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LM139 MD8 requirements.
6.How does Aetrix verify that LM139 MD8 is sourced from the original manufacturer or authorized distributors?
All LM139 MD8 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 LM139 MD8 meets industry standards.
7.What is the process for return or replacement of LM139 MD8?
All LM139 MD8 units undergo pre-shipment inspection (PSI). If there is an issue with LM139 MD8, 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 LM139 MD8 part is unused and in its original packaging.
Return procedure for LM139 MD8:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LM139 MD8 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
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