LM139JB Equivalent & Substitute Parts

Part Overview

The LM139JB is a quad differential comparator manufactured by Texas Instruments, designed for general-purpose comparison applications. This 14-pin CDIP through-hole component features open-collector and open-drain output stages, supporting a wide supply voltage range of 2V to 30V (single supply) or ±1V to ±15V (dual supply). The device is classified as Active product status and is RoHS3 compliant.

Substitute parts are identified when equivalent functional performance can be achieved within the specified electrical and mechanical parameters, accounting for differences in packaging technology, supply voltage ranges, and output stage configurations.

Substiute Parts

LM139JB

Texas InstrumentsIn Stock: 1527LM139JB Datasheet

Current PartRFQ

LM2901AQS14-13

Diodes IncorporatedIn Stock: 20116LM2901AQS14-13 Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the LM139JB is determined by the following critical parameters:

Functional Equivalence Criteria:

• Quad differential comparator configuration (4 elements minimum)
• Open-collector or open-drain output stage capability
• Supply voltage range overlap: minimum 2V to 30V single supply or ±1V to ±15V dual supply
• Input offset voltage within 5mV @ 5V specification
• Input bias current not exceeding 0.1µA @ 5V
• Output current capability of 16mA @ 5V or greater
• Quiescent current within 2.5mA maximum
• Operating temperature range including -55°C to 125°C or subset thereof

Packaging Considerations:

• Through-hole mounting (CDIP) or surface-mount alternatives (SOIC, SO) are acceptable for functional substitution
• Pin count must remain 14 pins
• Footprint compatibility depends on application PCB design

The LM2901AQS14-13 meets these criteria through equivalent quad comparator architecture, compatible output stages, and overlapping electrical specifications, despite differences in packaging technology and manufacturer.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitution Path:

The LM2901AQS14-13 (Diodes Incorporated) qualifies as a functional equivalent to the LM139JB based on:

1. Electrical Compatibility: All critical parameters meet or exceed LM139JB specifications. Input offset voltage (2mV) is superior to the 5mV maximum. Supply voltage range (2V–36V single, ±1V–18V dual) encompasses the LM139JB operating window. Output current capability (16mA) matches the original specification.

2. Functional Architecture: Both devices implement quad differential comparator topology with open-collector output capability, ensuring pin-compatible signal processing in existing circuit designs.

3. Compliance Status: Both parts maintain ROHS3 compliance and Active product status, ensuring continued availability and environmental regulatory alignment.

4. Packaging Trade-off: The LM2901AQS14-13 uses 14-SOIC surface-mount packaging versus the LM139JB's 14-CDIP through-hole format. This substitution requires PCB redesign for surface-mount assembly or use of through-hole adapter carriers.

5. Temperature Range Consideration: The LM2901AQS14-13 operates from -40°C to 125°C, which excludes the -55°C to -40°C range of the LM139JB. Applications requiring operation below -40°C must retain the original LM139JB or identify alternative parts with extended low-temperature specifications.

6. Automotive Qualification: The LM2901AQS14-13 carries AEC-Q100 automotive qualification, providing additional reliability assurance for automotive and harsh-environment applications.

Frequently Asked Questions (FAQ)

Q1: Can the LM2901AQS14-13 directly replace the LM139JB on an existing PCB?

A: Electrical substitution is valid; however, packaging differs. The LM139JB uses 14-CDIP through-hole mounting, while the LM2901AQS14-13 uses 14-SOIC surface-mount. Direct PCB replacement requires either PCB redesign for surface-mount assembly or use of a through-hole adapter carrier. Pin assignments remain compatible.

Q2: What are the key electrical differences between these parts?

A: The LM2901AQS14-13 provides superior input offset voltage (2mV versus 5mV) and supports a wider supply voltage range (2V–36V single supply versus 2V–30V). Input bias current is slightly higher (0.25µA versus 0.1µA) but remains within acceptable limits for most applications. Quiescent current is marginally higher (2.5mA versus 2mA).

Q3: Is the LM2901AQS14-13 suitable for low-temperature applications below -40°C?

A: No. The LM2901AQS14-13 operates from -40°C to 125°C, excluding temperatures below -40°C. The LM139JB supports -55°C to 125°C. Applications requiring operation at -55°C to -40°C must use the LM139JB or identify alternative parts with extended low-temperature ratings.

Q4: Does the LM2901AQS14-13 output stage configuration affect circuit design?

A: The LM2901AQS14-13 supports CMOS, MOS, open-collector, and TTL output options, compared to the LM139JB's open-collector and open-drain outputs. This expanded output capability provides design flexibility. Existing circuits designed for open-collector operation remain compatible.

Q5: What compliance certifications apply to both parts?

A: Both the LM139JB and LM2901AQS14-13 are ROHS3 compliant. The LM2901AQS14-13 additionally carries AEC-Q100 automotive qualification. Both parts are classified as Active products with continued manufacturing support.

Q6: Are there inventory or lead-time considerations?

A: The LM139JB has 1,462 pieces in stock. The LM2901AQS14-13 has 20,100 pieces in stock, indicating higher availability. Substitution may improve supply chain flexibility for high-volume production.