LM311N Equivalent & Substitute Parts

Part Overview

The LM311N is a single-channel voltage comparator manufactured by onsemi in 8-DIP through-hole packaging. This device is classified as obsolete, making equivalent and substitute parts necessary for new designs and production continuity. The LM311N operates across a wide supply voltage range and is suitable for general-purpose comparison applications requiring high-voltage operation. Substitute parts are selected based on functional equivalence in comparator topology, electrical performance parameters, and package compatibility.

Substiute Parts

LM311N

onsemiIn Stock: 7468LM311N Datasheet

Current PartRFQ

LM311N/NOPB

Texas InstrumentsIn Stock: 5394LM311N/NOPB Datasheet

DirectRFQ

AZV331KTR-G1

Diodes IncorporatedIn Stock: 26254AZV331KTR-G1 Datasheet

SimilarRFQ

LM311P

Texas InstrumentsIn Stock: 5406LM311P Datasheet

SimilarRFQ

LMV331IDCKR

Texas InstrumentsIn Stock: 65451LMV331IDCKR Datasheet

SimilarRFQ

LMV331IDCKT

Texas InstrumentsIn Stock: 2510LMV331IDCKT Datasheet

SimilarRFQ

LT1011ACN8#PBF

Analog Devices Inc.In Stock: 2436LT1011ACN8#PBF Datasheet

SimilarRFQ

LT1011CN8#PBF

Analog Devices Inc.In Stock: 1487LT1011CN8#PBF Datasheet

SimilarRFQ

LT1011CS8#TRPBF

Analog Devices Inc.In Stock: 3931LT1011CS8#TRPBF Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the LM311N is determined by the following criteria:

Primary Substitution Criteria:

• Comparator topology (single-channel, general-purpose)
• Output type compatibility (open-collector or multi-logic output)
• Supply voltage range overlap
• Input offset voltage and bias current specifications
• Package form factor (through-hole 8-DIP preferred; surface-mount alternatives acceptable with design modification)
• RoHS and REACH compliance status for modern production

Substitution Categories:

1. Direct Pin-Compatible Replacements (8-DIP Through-Hole): Parts maintaining identical pinout and package geometry, suitable for direct PCB substitution without layout changes.

2. Functional Equivalents with Package Variation (Surface-Mount): Parts providing equivalent electrical performance in alternative packages (SOT-23-5, SC-70-5, 8-SO), requiring PCB redesign or adapter solutions.

3. Enhanced Performance Variants: Parts with superior electrical characteristics (lower input offset voltage, lower bias current, faster propagation delay) within compatible package families.

Parameter Comparison

Engineering Selection Recommendations

For Direct Through-Hole Replacement (No PCB Redesign):

Select LM311N/NOPB (Texas Instruments) or LM311P (Texas Instruments) for pin-compatible substitution. Both maintain 8-DIP through-hole packaging and are actively produced with ROHS3 compliance. LM311N/NOPB provides the closest electrical match to the original onsemi part. LM311P operates within a slightly reduced supply voltage range (4.6V ~ 30V versus 5V ~ 36V) but remains suitable for most applications.

For Enhanced Performance with Through-Hole Compatibility:

LT1011ACN8#PBF and LT1011CN8#PBF (Analog Devices Inc.) offer superior electrical characteristics including lower input offset voltage (0.75mV to 2mV versus 7.5mV) and reduced quiescent current (4mA versus 7.5mA). Both maintain 8-DIP through-hole packaging and ROHS3 compliance. These parts are recommended when improved accuracy or lower power consumption is required.

For Surface-Mount Redesign:

LT1011CS8#TRPBF provides the same performance as LT1011CN8#PBF in 8-SO surface-mount packaging. LMV331IDCKT and LMV331IDCKR offer compact SC-70-5 packaging with extended operating temperature range (-40°C ~ 85°C) and are suitable for space-constrained applications. AZV331KTR-G1 (Diodes Incorporated) provides SOT-23-5 packaging with the widest availability (26,200 units in stock) but operates within a reduced supply voltage range (2.5V ~ 5.5V).

Compliance Considerations:

All recommended substitutes are ROHS3 compliant and REACH unaffected, meeting modern regulatory requirements. The original LM311N is RoHS non-compliant and should be replaced in new designs subject to RoHS directives.

Frequently Asked Questions (FAQ)

Q: Can I directly replace LM311N with LM311N/NOPB or LM311P without modifying my PCB?

A: Yes. Both LM311N/NOPB and LM311P maintain identical 8-DIP through-hole pinout and package geometry. No PCB layout changes are required. Verify that your supply voltage range falls within the specified limits (LM311N/NOPB: 5V ~ 36V; LM311P: 4.6V ~ 30V).

Q: What is the difference between LT1011ACN8#PBF and LT1011CN8#PBF?

A: Both are 8-DIP through-hole comparators from Analog Devices Inc. with identical package and mounting type. The primary difference is input offset voltage: LT1011ACN8#PBF specifies 0.75mV maximum at ±15V, while LT1011CN8#PBF specifies 2mV maximum. LT1011ACN8#PBF provides tighter offset tolerance and lower input bias current (0.035µA versus 0.065µA), making it suitable for precision applications.

Q: Can I use surface-mount alternatives like LMV331IDCKT or AZV331KTR-G1 as direct replacements?

A: No. Surface-mount parts require PCB redesign and cannot be used in through-hole sockets. However, they provide functional equivalence and are suitable for new designs. LMV331IDCKT and LMV331IDCKR operate within a reduced supply voltage range (2.7V ~ 5.5V) compared to the original LM311N (5V ~ 36V). Verify compatibility with your application's supply voltage before selection.

Q: What is the supply voltage range limitation of AZV331KTR-G1?

A: AZV331KTR-G1 operates within 2.5V ~ 5.5V single supply or equivalent dual supply. This is significantly narrower than the original LM311N (5V ~ 36V). This part is suitable only for low-voltage applications. Do not use if your design requires operation above 5.5V.

Q: Are all substitute parts RoHS compliant?

A: Yes. All recommended substitute parts carry ROHS3 compliance status. The original LM311N is RoHS non-compliant. Substitution is necessary for designs subject to RoHS directives or customer requirements.

Q: Which substitute offers the best stock availability?

A: AZV331KTR-G1 (Diodes Incorporated) has the highest inventory at 26,200 units in stock. However, verify supply voltage compatibility (2.5V ~ 5.5V) before selection. For through-hole applications, LMV331IDCKR offers 65,400 units in stock but requires surface-mount PCB design.

Q: What is the operating temperature range difference between LM311N and modern substitutes?

A: The original LM311N operates 0°C ~ 70°C. Modern substitutes from Texas Instruments and Analog Devices maintain this range for 8-DIP variants. Surface-mount alternatives (LMV331IDCKT, AZV331KTR-G1) extend the range to -40°C ~ 85°C, suitable for industrial and automotive applications.