LM139W Equivalent & Substitute Parts Reference

Part Overview

The LM139W is a quad differential comparator manufactured by Texas Instruments, designed for general-purpose comparison applications. This 14-pin surface-mount device operates across a wide supply voltage range (2V to 30V single supply, ±1V to ±15V dual supply) and features open-collector, open-drain output configuration. The device is classified as Active product status with full RoHS3 compliance. Substitute parts are identified when equivalent functional performance is required due to inventory constraints, application-specific packaging needs, or supply chain considerations while maintaining electrical and mechanical compatibility within specified parameter tolerances.

Substiute Parts

LM139W

Texas InstrumentsIn Stock: 1353LM139W Datasheet

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LM2901AS14-13

Diodes IncorporatedIn Stock: 12770LM2901AS14-13 Datasheet

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LM2901QS14-13

Diodes IncorporatedIn Stock: 17638LM2901QS14-13 Datasheet

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LM2901QT14-13

Diodes IncorporatedIn Stock: 7691LM2901QT14-13 Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the LM139W is determined by the following critical parameters:

Functional Equivalence Criteria:

• Quad differential comparator configuration (4 elements)
• General-purpose comparator type
• Supply voltage range compatibility: minimum 2V single supply or ±1V dual supply capability
• Output current capability: 16mA typical at 5V
• Operating temperature range: minimum -40°C to 125°C (LM139W operates -55°C to 125°C)

Mechanical Compatibility Criteria:

• Surface-mount packaging only (14-pin configurations)
• Pin count: 14 pins
• RoHS3 compliance required

Acceptable Parameter Variations:

• Input offset voltage: up to 7mV @ 5V (LM139W specifies 5mV maximum)
• Input bias current: up to 0.25µA @ 5V (LM139W specifies 0.1µA maximum)
• Quiescent current: up to 2.5mA (LM139W specifies 2mA maximum)
• Supply voltage range: extended to 36V single supply or ±18V dual supply acceptable
• Output type: CMOS/TTL output acceptable as functional alternative to open-collector/open-drain

The three identified substitute parts (LM2901AS14-13, LM2901QS14-13, LM2901QT14-13) meet all functional equivalence and mechanical compatibility criteria within specified parameter tolerances.

Parameter Comparison

Engineering Selection Recommendations

LM2901AS14-13 (Diodes Incorporated, 14-SOIC)

This substitute offers the tightest input offset voltage specification (2mV @ 5V), exceeding the LM139W performance. Extended supply voltage range (2V to 36V single, ±1V to ±18V dual) provides additional design margin. Operating temperature range (-40°C to 125°C) is narrower than the main part but suitable for standard industrial applications. 14-SOIC package is a standard surface-mount configuration with 12,700 units in stock. RoHS3 compliance maintained. Selection appropriate when superior input offset performance is required and lower temperature extremes are not critical.

LM2901QS14-13 (Diodes Incorporated, 14-SOIC, Automotive Grade)

This variant includes AEC-Q100 automotive qualification and CMOS/TTL output configuration. Input offset voltage specification (7mV @ 5V) remains within acceptable tolerance. Moisture sensitivity level MSL-1 (Unlimited) indicates superior moisture resistance compared to standard industrial grades. Operating temperature range (-40°C to 125°C) and extended supply voltage range (2V to 36V single, ±1V to ±18V dual) match LM2901AS14-13. Highest inventory availability (17,600 units). Selection appropriate for automotive applications or when enhanced reliability and moisture resistance are required.

LM2901QT14-13 (Diodes Incorporated, 14-TSSOP, Automotive Grade)

This variant provides identical electrical specifications to LM2901QS14-13 with AEC-Q100 automotive qualification and MSL-1 moisture sensitivity rating. Distinguishing feature is 14-TSSOP package (0.173", 4.40mm width) versus 14-SOIC. TSSOP package offers reduced board footprint and improved thermal characteristics for space-constrained applications. Operating temperature range (-40°C to 125°C) and supply voltage range (2V to 36V single, ±1V to ±18V dual) identical to other LM2901 variants. Inventory: 7,600 units. Selection appropriate when compact package geometry is required without compromising electrical performance or reliability.

Frequently Asked Questions (FAQ)

Q: Can LM2901AS14-13, LM2901QS14-13, or LM2901QT14-13 directly replace LM139W in existing designs?

A: Electrical substitution is valid within specified parameter tolerances. All three parts maintain quad differential comparator functionality, 16mA output current capability, and compatible supply voltage ranges. Package differences (CFlatPack versus SOIC/TSSOP) require PCB layout modification. Pin-to-pin compatibility must be verified against specific board design.

Q: What is the significance of the operating temperature range difference (-55°C to 125°C versus -40°C to 125°C)?

A: The LM139W operates across a wider temperature range, including extended low-temperature operation to -55°C. Substitute parts operate from -40°C minimum. Selection of substitutes is appropriate for applications with operating temperature floor of -40°C or higher. Applications requiring -55°C operation must retain the LM139W.

Q: How do CMOS/TTL output types on LM2901QS14-13 and LM2901QT14-13 differ from the open-collector, open-drain output of LM139W?

A: Open-collector/open-drain outputs require external pull-up resistors and are suitable for wired-OR logic and multi-voltage interface applications. CMOS/TTL outputs provide active high and low drive capability without external pull-ups. Circuit-level compatibility depends on application requirements. Open-collector/open-drain functionality is preferred for applications requiring wired logic or multi-voltage operation.

Q: What packaging considerations apply when substituting LM139W with LM2901 variants?

A: LM139W uses 14-CFlatPack (ceramic flat pack). LM2901AS14-13 and LM2901QS14-13 use 14-SOIC (0.154", 3.90mm width). LM2901QT14-13 uses 14-TSSOP (0.173", 4.40mm width). All are surface-mount configurations with identical 14-pin count. PCB footprint, solder reflow profile, and thermal management characteristics differ. Board redesign is required for package substitution.

Q: Are all substitute parts RoHS3 compliant?

A: Yes. LM139W, LM2901AS14-13, LM2901QS14-13, and LM2901QT14-13 are all ROHS3 compliant. Environmental compliance is maintained across all substitution options.

Q: What is the significance of AEC-Q100 qualification on LM2901QS14-13 and LM2901QT14-13?

A: AEC-Q100 is the automotive electronics council qualification standard for integrated circuits. Parts meeting this qualification have undergone rigorous testing for automotive applications including temperature cycling, humidity resistance, and reliability verification. Selection of AEC-Q100 qualified parts is required for automotive applications or when enhanced reliability documentation is necessary.

Q: How do input offset voltage specifications affect circuit performance?

A: Input offset voltage determines the maximum error in comparator threshold accuracy. LM139W specifies 5mV maximum at 5V. LM2901AS14-13 specifies 2mV (superior performance). LM2901QS14-13 and LM2901QT14-13 specify 7mV (acceptable tolerance). For precision threshold applications, LM2901AS14-13 offers tighter accuracy. For standard applications, all variants remain within acceptable tolerance.

Q: What inventory considerations apply to these substitute parts?

A: LM139W: 1,262 units in stock. LM2901AS14-13: 12,700 units. LM2901QS14-13: 17,600 units (highest availability). LM2901QT14-13: 7,600 units. Substitute selection may be driven by inventory availability and supply chain requirements.