LMC7221AIMX Equivalent & Substitute Parts

Part Overview

The LMC7221AIMX is a general-purpose comparator IC manufactured by Texas Instruments, housed in an 8-SOIC surface-mount package. This device features open-drain output configuration and operates across a wide supply voltage range of 2.7V to 15V (single supply) or ±1.35V to ±7.5V (dual supply). The LMC7221AIMX is classified as obsolete, making identification of equivalent and substitute parts essential for ongoing design support and production continuity.

Substiute Parts

LMC7221AIMX

Texas InstrumentsIn Stock: 2139LMC7221AIMX Datasheet

Current PartRFQ

LMC7221AIMX/NOPB

Texas InstrumentsIn Stock: 3873LMC7221AIMX/NOPB Datasheet

Parametric EquivalentRFQ

ADCMP391ARZ

Analog Devices Inc.In Stock: 9422ADCMP391ARZ Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the LMC7221AIMX are identified based on the following critical parameters that determine functional compatibility:

• Package Type: All substitutes must use 8-SOIC surface-mount packaging to ensure PCB layout compatibility
• Functional Category: General-purpose comparator with single-element configuration
• Supply Voltage Range: Compatibility within the specified voltage operating window
• Output Configuration: Open-drain or rail-to-rail output types suitable for the application
• Electrical Performance: Input offset voltage, input bias current, propagation delay, and quiescent current within acceptable ranges
• Temperature Range: Operating temperature specifications must support the required thermal environment

Two substitute parts are identified: LMC7221AIMX/NOPB (parametric equivalent from Texas Instruments) and ADCMP391ARZ (manufacturer-recommended alternative from Analog Devices Inc.).

Parameter Comparison

Engineering Selection Recommendations

LMC7221AIMX/NOPB is the direct parametric equivalent and preferred substitute. This part maintains identical electrical specifications and operating characteristics while offering active product status and ROHS3 compliance. The packaging format (Tape & Reel) supports high-volume production requirements. Selection of this part eliminates obsolescence risk while preserving design compatibility.

ADCMP391ARZ is a manufacturer-recommended alternative from Analog Devices Inc. This substitute introduces design trade-offs that must be evaluated against application requirements. The ADCMP391ARZ features a narrower supply voltage range (2.3V ~ 5.5V) compared to the LMC7221AIMX (2.7V ~ 15V), which may restrict applicability in designs requiring extended voltage operation. The ADCMP391ARZ offers superior propagation delay performance (4.2µs versus 10µs) and lower input offset voltage (2.5mV versus 5mV), beneficial for high-speed or precision applications. The rail-to-rail output configuration differs from the open-drain output of the original part, requiring circuit topology verification. Extended operating temperature range (-40°C ~ 125°C) provides thermal margin beyond the original specification. ROHS3 compliance and active product status ensure long-term availability.

Frequently Asked Questions (FAQ)

Q: Can LMC7221AIMX/NOPB be used as a direct drop-in replacement for LMC7221AIMX?

A: Yes. LMC7221AIMX/NOPB is a parametric equivalent with identical electrical specifications, operating temperature range, and 8-SOIC package configuration. The primary difference is product status (active versus obsolete) and packaging format (Tape & Reel versus bulk). No circuit modifications are required.

Q: What are the key differences between LMC7221AIMX and ADCMP391ARZ?

A: The ADCMP391ARZ differs in four critical areas: (1) Supply voltage range is narrower (2.3V ~ 5.5V versus 2.7V ~ 15V), (2) Output type is rail-to-rail instead of open-drain, (3) Propagation delay is faster (4.2µs versus 10µs), and (4) Operating temperature range is extended (-40°C ~ 125°C versus -40°C ~ 85°C). Circuit topology verification is required before substitution.

Q: Is the ADCMP391ARZ suitable for applications requiring open-drain output?

A: The ADCMP391ARZ features rail-to-rail output configuration, which differs from the open-drain output of the LMC7221AIMX. Applications dependent on open-drain output characteristics require circuit redesign or selection of LMC7221AIMX/NOPB.

Q: What is the impact of the narrower supply voltage range in ADCMP391ARZ?

A: The ADCMP391ARZ operates within 2.3V ~ 5.5V, whereas the LMC7221AIMX supports 2.7V ~ 15V. Designs requiring supply voltages above 5.5V or below 2.3V cannot use the ADCMP391ARZ without circuit modification. Verify supply voltage requirements before substitution.

Q: Are both substitute parts RoHS compliant?

A: Yes. LMC7221AIMX/NOPB and ADCMP391ARZ are both ROHS3 compliant. The original LMC7221AIMX is RoHS non-compliant. Compliance requirements may influence part selection for regulated applications.

Q: What packaging formats are available for these substitutes?

A: LMC7221AIMX/NOPB is supplied in Tape & Reel (TR) format, suitable for automated assembly. ADCMP391ARZ is supplied in Tube format. Packaging selection depends on production volume and assembly equipment compatibility.