LMH6640MF Equivalent & Substitute Parts

Part Overview

The LMH6640MF is a voltage feedback operational amplifier manufactured by Texas Instruments, housed in a SOT-23-5 surface mount package. This device is classified as obsolete, indicating it is no longer in active production. The LMH6640MF features rail-to-rail output capability with a single amplifier circuit, designed for applications requiring high-speed voltage feedback amplification.

Due to its obsolete status, locating new original inventory of the LMH6640MF presents supply chain challenges. Equivalent and substitute parts are necessary to maintain design continuity and ensure long-term component availability for production and repair applications.

Substiute Parts

LMH6640MF

Texas InstrumentsIn Stock: 2494LMH6640MF Datasheet

Current PartRFQ

LMH6642MF/NOPB

Texas InstrumentsIn Stock: 38368LMH6642MF/NOPB Datasheet

MFR RecommendedRFQ

MCP6H01T-E/OT

Microchip TechnologyIn Stock: 2081MCP6H01T-E/OT Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the LMH6640MF is determined by compatibility across the following critical parameters:

Package Compatibility: All substitute parts must use the SOT-23-5 surface mount package to ensure direct board-level compatibility without layout modifications.

Functional Classification: The LMH6640MF is a voltage feedback amplifier with rail-to-rail output. Substitute parts must maintain these core functional characteristics.

Electrical Performance Envelope: Substitute parts must operate within the specified supply voltage range (4.5 V to 16 V minimum) and support the operating temperature range (-40°C to 85°C minimum).

Single Circuit Configuration: All substitutes must contain exactly one amplifier circuit per package.

The LMH6642MF/NOPB is a manufacturer-recommended substitute from Texas Instruments, maintaining the same voltage feedback architecture and package format while offering active product status and improved compliance certifications. The MCP6H01T-E/OT is a general-purpose amplifier alternative from Microchip Technology that provides rail-to-rail output in the same package, though with different performance characteristics suited to lower-speed applications.

Parameter Comparison

Engineering Selection Recommendations

LMH6642MF/NOPB (Primary Substitute): This Texas Instruments part is the manufacturer-recommended substitute for the LMH6640MF. It maintains voltage feedback amplifier architecture and identical package format. The LMH6642MF/NOPB carries active product status, ensuring long-term availability and supply chain stability. It is ROHS3 compliant, meeting modern environmental and regulatory requirements. Performance characteristics are closely aligned with the original part, with slightly reduced slew rate (135 V/µs versus 170 V/µs) and -3dB bandwidth (130 MHz versus 190 MHz). Supply voltage range is narrower (2.7 V to 12.8 V versus 4.5 V to 16 V), requiring verification against specific application requirements. Current consumption is lower (2.7 mA versus 4 mA), and output current capability is reduced (75 mA versus 100 mA).

MCP6H01T-E/OT (Alternative Substitute): This Microchip Technology part provides a general-purpose amplifier alternative in the same SOT-23-5 package. It is active in production and ROHS3 compliant. The MCP6H01T-E/OT operates across a wider supply voltage range (3.5 V to 16 V) and extended temperature range (-40°C to 125°C). However, this part exhibits significantly lower performance specifications: slew rate of 0.8 V/µs and gain bandwidth product of 1.2 MHz. The MCP6H01T-E/OT is suitable only for low-frequency, low-speed applications and is not appropriate for designs requiring the high-speed characteristics of the original LMH6640MF.

Frequently Asked Questions (FAQ)

Q: Can the LMH6642MF/NOPB be used as a direct replacement for the LMH6640MF?

A: The LMH6642MF/NOPB is compatible at the package level (SOT-23-5) and maintains the same voltage feedback amplifier architecture. However, performance differences exist. The slew rate is reduced from 170 V/µs to 135 V/µs, and the -3dB bandwidth decreases from 190 MHz to 130 MHz. The supply voltage range is narrower (2.7 V to 12.8 V versus 4.5 V to 16 V). Applications operating at the upper supply voltage limit (above 12.8 V) or requiring maximum slew rate performance require circuit evaluation before substitution.

Q: Is the MCP6H01T-E/OT suitable for high-speed applications?

A: No. The MCP6H01T-E/OT is a general-purpose amplifier with a slew rate of 0.8 V/µs and gain bandwidth product of 1.2 MHz. These specifications are approximately 200 times lower than the LMH6640MF. This part is appropriate only for DC and low-frequency signal conditioning applications. Applications requiring the high-speed performance of the LMH6640MF must use the LMH6642MF/NOPB or equivalent high-speed voltage feedback amplifiers.

Q: What are the compliance differences between these parts?

A: The LMH6640MF is RoHS non-compliant. Both the LMH6642MF/NOPB and MCP6H01T-E/OT are ROHS3 compliant, meeting current environmental regulations. All three parts have MSL rating of 1 (Unlimited) and are REACH unaffected. For applications subject to RoHS requirements, the LMH6642MF/NOPB or MCP6H01T-E/OT must be selected.

Q: Are there supply voltage compatibility issues?

A: Yes. The LMH6640MF operates from 4.5 V to 16 V. The LMH6642MF/NOPB operates from 2.7 V to 12.8 V, which is narrower at the upper limit. Applications using supply voltages between 12.8 V and 16 V cannot use the LMH6642MF/NOPB. The MCP6H01T-E/OT operates from 3.5 V to 16 V, covering the full upper range but with significantly reduced performance.

Q: What is the impact of reduced output current capability?

A: The LMH6640MF provides 100 mA output current per channel. The LMH6642MF/NOPB provides 75 mA. Applications requiring output currents above 75 mA must use the original LMH6640MF or alternative high-current amplifiers. The MCP6H01T-E/OT does not specify output current capability and is unsuitable for current-driving applications.

Q: How do input bias current specifications compare?

A: The LMH6640MF has 1 µA input bias current. The LMH6642MF/NOPB has 1.6 µA. The MCP6H01T-E/OT has 10 pA, which is significantly lower. For applications sensitive to input bias current effects, the MCP6H01T-E/OT provides superior performance, though its low-speed characteristics limit its use to DC and very low-frequency circuits.

Q: What is the operating temperature range consideration?

A: The LMH6640MF and LMH6642MF/NOPB both operate from -40°C to 85°C. The MCP6H01T-E/OT extends to -40°C to 125°C. Applications requiring operation above 85°C must use the MCP6H01T-E/OT, accepting the performance trade-offs associated with general-purpose amplifier architecture.

Q: Are there any packaging or board-level compatibility concerns?

A: All three parts use the SOT-23-5 package (SC-74A, SOT-753). Pin-to-pin compatibility is maintained, allowing direct board-level substitution without layout modifications. Moisture sensitivity level is identical (MSL 1, Unlimited) for all parts.