LMH6644MT Equivalent & Substitute Parts

Part Overview

The LMH6644MT is a voltage feedback operational amplifier featuring four independent circuits in a 14-TSSOP surface mount package. This device is designed for rail-to-rail output applications with high-speed performance characteristics. The LMH6644MT carries an obsolete product status from Texas Instruments, making identification of equivalent and substitute parts essential for ongoing design support, production continuity, and component procurement.

Substiute Parts

LMH6644MT

Texas InstrumentsIn Stock: 18796LMH6644MT Datasheet

Current PartRFQ

LMH6644MT/NOPB

Texas InstrumentsIn Stock: 1275LMH6644MT/NOPB Datasheet

DirectRFQ

NCV33204DTBR2G

onsemiIn Stock: 19127NCV33204DTBR2G Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the LMH6644MT is determined by the following critical parameters:

Package Compatibility: All substitute parts must use the 14-TSSOP surface mount package to ensure mechanical and electrical compatibility with existing PCB layouts.

Circuit Configuration: The four-circuit configuration is a fundamental requirement. Substitute parts must provide four independent operational amplifier circuits within a single package.

Output Architecture: Rail-to-rail output capability is essential for applications requiring maximum signal swing within the supply voltage range.

Electrical Performance Envelope: Substitute parts must operate within the specified supply voltage range (2.7 V to 12.8 V minimum) and support the operating temperature range of -40°C to 85°C.

Amplifier Classification: Both voltage feedback and general purpose amplifier types are acceptable within this substitution category, as both architectures support the required functional performance in 14-TSSOP quad-channel configurations.

Substitutes are grouped into two categories: direct equivalents (identical part number variants with different packaging or compliance status) and manufacturer-recommended alternatives (functionally compatible parts from different manufacturers with comparable electrical characteristics).

Parameter Comparison

Engineering Selection Recommendations

LMH6644MT/NOPB (Direct Equivalent)

The LMH6644MT/NOPB is the direct equivalent of the LMH6644MT, manufactured by Texas Instruments with identical electrical specifications and package configuration. The primary distinction is product status: LMH6644MT/NOPB carries active product status, ensuring ongoing availability and manufacturing support. This part is ROHS3 compliant, addressing regulatory requirements for new designs. The /NOPB designation indicates lead-free, halogen-free packaging. For applications currently using the obsolete LMH6644MT, transition to LMH6644MT/NOPB provides continuity with no design modifications required.

NCV33204DTBR2G (Manufacturer-Recommended Alternative)

The NCV33204DTBR2G is an onsemi general purpose operational amplifier with active product status and AEC-Q100 automotive qualification. This part maintains the 14-TSSOP package, four-circuit configuration, and rail-to-rail output architecture. Key differences include lower slew rate (1 V/µs versus 135 V/µs), reduced bandwidth (2.2 MHz versus 130 MHz), lower input bias current (80 nA versus 1.6 µA), and significantly reduced supply current (0.9 mA versus 2.7 mA for four channels). The NCV33204DTBR2G operates across an extended temperature range (-55°C to 125°C) and supports lower minimum supply voltage (1.8 V). Selection of this alternative requires verification that the reduced bandwidth and slew rate are compatible with the target application's frequency response and signal conditioning requirements.

Frequently Asked Questions (FAQ)

Q: Can LMH6644MT/NOPB be used as a direct replacement for LMH6644MT?

A: Yes. The LMH6644MT/NOPB is electrically and mechanically identical to the LMH6644MT. Both parts share identical electrical specifications, package configuration, and pin assignments. The primary advantage of LMH6644MT/NOPB is active product status and ROHS3 compliance. No circuit modifications or PCB layout changes are required for substitution.

Q: What are the key performance differences between LMH6644MT and NCV33204DTBR2G?

A: The LMH6644MT provides significantly higher slew rate (135 V/µs versus 1 V/µs) and bandwidth (130 MHz versus 2.2 MHz). The LMH6644MT exhibits higher input bias current (1.6 µA versus 80 nA) and higher supply current consumption (2.7 mA versus 0.9 mA for four channels). The NCV33204DTBR2G supports lower minimum supply voltage (1.8 V versus 2.7 V) and extended operating temperature range (-55°C to 125°C versus -40°C to 85°C). Selection depends on application bandwidth and speed requirements.

Q: Are all substitute parts available in the same 14-TSSOP package?

A: Yes. All parts listed—LMH6644MT, LMH6644MT/NOPB, and NCV33204DTBR2G—use the 14-TSSOP surface mount package with identical mechanical dimensions (0.173" width, 4.40mm). PCB footprints and land patterns are compatible across all three parts.

Q: Which substitute part is recommended for new designs?

A: For new designs requiring the electrical performance characteristics of the original LMH6644MT, use LMH6644MT/NOPB. This part provides identical performance with active product status and modern compliance certifications. For applications with reduced bandwidth and speed requirements, NCV33204DTBR2G offers lower power consumption and extended temperature range with automotive qualification.

Q: Is the NCV33204DTBR2G suitable for high-frequency signal conditioning applications?

A: The NCV33204DTBR2G bandwidth of 2.2 MHz is significantly lower than the LMH6644MT bandwidth of 130 MHz. Applications requiring high-frequency response, fast transient handling, or high slew rate performance should use LMH6644MT or LMH6644MT/NOPB. The NCV33204DTBR2G is suitable for low-frequency general purpose amplification, sensor signal conditioning, and audio-range applications.

Q: What is the significance of the /NOPB designation on LMH6644MT/NOPB?

A: The /NOPB designation indicates lead-free, halogen-free packaging that complies with ROHS3 environmental regulations. This designation does not affect electrical performance or pin compatibility. The /NOPB variant is required for applications subject to RoHS compliance mandates in the European Union and other regulated markets.