LMC7221AIM Equivalent & Substitute Parts

Part Overview

The LMC7221AIM 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 LMC7221AIM is classified as obsolete, making identification of functionally equivalent alternatives essential for ongoing design support and production continuity.

Substiute Parts

LMC7221AIM

Texas InstrumentsIn Stock: 2604LMC7221AIM Datasheet

Current PartRFQ

LMC7221AIM/NOPB

Texas InstrumentsIn Stock: 1260LMC7221AIM/NOPB Datasheet

DirectRFQ

ADCMP391ARZ

Analog Devices Inc.In Stock: 9422ADCMP391ARZ Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the LMC7221AIM is determined by the following critical parameters:

Package Compatibility: All substitute parts must use the 8-SOIC surface-mount package to ensure mechanical and electrical compatibility with existing PCB layouts.

Functional Classification: Substitute parts must be general-purpose comparators capable of operating as single-element devices.

Supply Voltage Range: Substitute parts must support the application's required supply voltage configuration. The LMC7221AIM operates at 2.7V to 15V (single supply) or ±1.35V to ±7.5V (dual supply).

Output Configuration: The open-drain output type of the LMC7221AIM defines a primary substitution criterion. Parts with alternative output types (such as rail-to-rail) may function in applications with appropriate pull-up resistor configurations but represent a design variation.

Operating Temperature Range: The -40°C to 85°C operating range must be met or exceeded by substitute parts.

Compliance Status: RoHS and REACH compliance status should be evaluated based on production requirements and regulatory jurisdiction.

Parameter Comparison

Engineering Selection Recommendations

LMC7221AIM/NOPB (Direct Substitute): This part is the active production equivalent of the obsolete LMC7221AIM. Both devices share identical electrical specifications, package configuration, and output type. The primary distinction is product status and compliance: LMC7221AIM/NOPB is active and ROHS3 compliant, whereas the original LMC7221AIM is obsolete and RoHS non-compliant. For applications requiring the exact electrical and mechanical characteristics of the LMC7221AIM, LMC7221AIM/NOPB is the recommended direct replacement.

ADCMP391ARZ (Functional Substitute): The ADCMP391ARZ is an active, ROHS3-compliant comparator from Analog Devices Inc. that shares the 8-SOIC package and general-purpose comparator classification. However, this device differs in three key aspects: (1) output type is rail-to-rail rather than open-drain, (2) supply voltage range is limited to 2.3V to 5.5V, and (3) operating temperature range extends to 125°C. The ADCMP391ARZ offers superior propagation delay (4.2µs versus 10µs) and lower input offset voltage (2.5mV versus 5mV). Selection of ADCMP391ARZ requires verification that the application's supply voltage does not exceed 5.5V and that the rail-to-rail output configuration is compatible with the existing circuit design.

Frequently Asked Questions (FAQ)

Q: Can LMC7221AIM/NOPB be used as a direct replacement for LMC7221AIM?

A: Yes. LMC7221AIM/NOPB is the active production equivalent with identical electrical specifications, package type, and output configuration. The primary differences are product status (active versus obsolete) and RoHS compliance (ROHS3 compliant versus non-compliant). No circuit modifications are required.

Q: What are the limitations of using ADCMP391ARZ as a substitute?

A: The ADCMP391ARZ has a narrower supply voltage range (2.3V to 5.5V versus 2.7V to 15V) and uses rail-to-rail output instead of open-drain. Applications requiring supply voltages above 5.5V or those dependent on open-drain output characteristics cannot use this device without circuit redesign.

Q: Are all substitute parts available in the same packaging?

A: Yes. LMC7221AIM/NOPB and ADCMP391ARZ are both supplied in 8-SOIC surface-mount packages with identical physical dimensions (0.154" width, 3.90mm). PCB layout compatibility is maintained across all three parts.

Q: What is the impact of output type differences between LMC7221AIM and ADCMP391ARZ?

A: The LMC7221AIM uses open-drain output, which requires an external pull-up resistor to establish a high logic level. The ADCMP391ARZ uses rail-to-rail output, which can drive logic levels directly to the supply rails without external pull-up components. Circuit topology must be evaluated to determine compatibility.

Q: Which substitute is recommended for new designs?

A: For applications matching the LMC7221AIM's supply voltage range and open-drain output requirements, LMC7221AIM/NOPB is the recommended choice due to electrical equivalence and active product status. For applications with supply voltages limited to 5.5V or lower, ADCMP391ARZ offers improved performance characteristics and extended operating temperature range.