LM311PWR Equivalent & Substitute Parts

Part Overview

The LM311PWR is a general-purpose comparator IC manufactured by Texas Instruments, housed in an 8-TSSOP surface-mount package. This device operates across a wide supply voltage range of 4.6V to 30V (single supply) or ±1.75V to ±15V (dual supply), making it suitable for analog signal comparison applications in industrial and commercial environments. The part is currently active in production with ROHS3 compliance and unlimited moisture sensitivity rating. Substitute parts are identified when equivalent functional performance can be maintained within the specified electrical and mechanical parameters while accommodating different packaging or operational grade requirements.

Substiute Parts

LM311PWR

Texas InstrumentsIn Stock: 5728LM311PWR Datasheet

Current PartRFQ

LM211QDRQ1

Texas InstrumentsIn Stock: 20181LM211QDRQ1 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the LM311PWR is determined by equivalence in the following critical parameters:

• Functional Type: General-purpose comparator with identical output type configuration (DTL, MOS, Open-Collector, Open-Emitter, RTL, TTL)
• Supply Voltage Compatibility: Identical operating range of 4.6V ~ 30V (single) or ±1.75V ~ ±15V (dual)
• Output Current Capability: Minimum 50mA typical output current
• Quiescent Current: Maximum 7.5mA or lower
• Input Offset Voltage: Maximum 7.5mV or lower at ±15V
• Input Bias Current: Maximum 0.25µA or lower at ±15V
• Base Product Number: LM211 series maintains functional equivalence
• Compliance: ROHS3 compliant, REACH unaffected

The LM211QDRQ1 qualifies as a manufacturer-recommended substitute based on these parameters, with the primary difference being package format (8-SOIC vs. 8-TSSOP) and extended operating temperature range with automotive qualification.

Parameter Comparison

Engineering Selection Recommendations

LM311PWR remains the primary selection for applications requiring the 8-TSSOP package format with commercial-grade operating temperature range (0°C ~ 70°C). This part is actively produced and maintains full ROHS3 and REACH compliance.

LM211QDRQ1 is the manufacturer-recommended substitute when:

• The 8-SOIC package format is compatible with PCB layout and assembly processes
• Extended operating temperature range (-40°C ~ 125°C) is required for industrial or automotive environments
• Improved input offset voltage (3mV vs. 7.5mV) and input bias current (0.1µA vs. 0.25µA) specifications provide performance margin
• Automotive-grade qualification (AEC-Q100) is required for vehicle or harsh-environment applications
• Lower quiescent current (6mA vs. 7.5mA) is beneficial for power-constrained designs

Both parts share identical functional performance in core comparator operation, supply voltage compatibility, and output current capability. Package selection and operating temperature requirements are the primary differentiators.

Frequently Asked Questions (FAQ)

Q: Can LM211QDRQ1 be used as a direct replacement for LM311PWR in existing designs?

A: Functional substitution is possible if the 8-SOIC package footprint can be accommodated on the PCB. The electrical performance is equivalent or superior. However, PCB layout modifications are required due to different package dimensions (8-SOIC: 0.154" width vs. 8-TSSOP: 0.173" width). Verify that the extended operating temperature range (-40°C ~ 125°C) does not conflict with design specifications if the original application was limited to 0°C ~ 70°C.

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

A: The LM211QDRQ1 provides superior specifications in three areas: input offset voltage (3mV vs. 7.5mV), input bias current (0.1µA vs. 0.25µA), and quiescent current (6mA vs. 7.5mA). Supply voltage range, output current, and output type configuration are identical. These improvements make LM211QDRQ1 suitable for precision analog applications requiring tighter input specifications.

Q: Are both parts RoHS and REACH compliant?

A: Yes. Both LM311PWR and LM211QDRQ1 are ROHS3 compliant and REACH unaffected, with unlimited moisture sensitivity rating (MSL 1). Both are suitable for applications requiring environmental compliance certification.

Q: What is the significance of the automotive qualification on LM211QDRQ1?

A: The LM211QDRQ1 carries AEC-Q100 automotive qualification, indicating it has been tested and validated for automotive-grade reliability and temperature cycling. This qualification is required for vehicle applications and harsh industrial environments. The LM311PWR does not carry this qualification and is suitable for commercial-grade applications only.

Q: Can I use LM311PWR in applications requiring -40°C ~ 125°C operating temperature?

A: No. The LM311PWR is specified for 0°C ~ 70°C operation only. For extended temperature range applications, LM211QDRQ1 (-40°C ~ 125°C) is the appropriate selection.

Q: Are there any supply voltage or output type differences between these parts?

A: No. Both parts support identical supply voltage ranges (4.6V ~ 30V single supply or ±1.75V ~ ±15V dual supply) and identical output type configurations (DTL, MOS, Open-Collector, Open-Emitter, RTL, TTL). Substitution does not affect voltage compatibility or output interface requirements.