LMH6645MFX Equivalent & Substitute Parts

Part Overview

The LMH6645MFX is a voltage feedback operational amplifier manufactured by Texas Instruments, designed for single-circuit push-pull, rail-to-rail applications in surface mount SOT-23-5 packaging. This device is classified as obsolete, which necessitates identification of active equivalent parts for new designs and ongoing production requirements. The LMH6645MFX operates across a 2.5V to 12V supply range with a 55 MHz bandwidth and 22V/µs slew rate, making it suitable for general-purpose signal conditioning and amplification circuits.

Substiute Parts

LMH6645MFX

Texas InstrumentsIn Stock: 2522LMH6645MFX Datasheet

Current PartRFQ

LMH6645MFX/NOPB

Texas InstrumentsIn Stock: 45290LMH6645MFX/NOPB Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the LMH6645MFX is determined by electrical and mechanical parameter equivalence across the following criteria:

Electrical Parameters: Voltage feedback amplifier topology with single circuit configuration, push-pull rail-to-rail output stage, 22V/µs slew rate, 55 MHz bandwidth, 650 nA input bias current, 1 mV input offset voltage, 725 µA supply current, and 20 mA output current per channel.

Supply Voltage Compatibility: Operating range from 2.5V minimum to 12V maximum supply span.

Thermal Specifications: Operating temperature range of -40°C to 85°C.

Mechanical Parameters: Surface mount packaging in SC-74A / SOT-753 form factor (SOT-23-5 supplier device package).

Compliance and Status: Product status and regulatory compliance certifications determine suitability for new designs versus legacy system maintenance.

Parameter Comparison

Engineering Selection Recommendations

The LMH6645MFX/NOPB is the direct active equivalent for the obsolete LMH6645MFX. Both parts share identical electrical specifications, thermal operating range, and mechanical packaging. The primary distinction is product status and regulatory compliance.

For New Designs: The LMH6645MFX/NOPB is the appropriate selection. This part carries active product status from Texas Instruments and meets RoHS3 compliance requirements, ensuring long-term availability and regulatory alignment for production systems.

For Legacy System Maintenance: The LMH6645MFX remains functionally equivalent for existing applications where RoHS compliance is not mandated. However, availability is limited to existing inventory, and transition to the LMH6645MFX/NOPB is recommended for continuity planning.

Compliance Considerations: The LMH6645MFX/NOPB carries RoHS3 compliance certification, whereas the original LMH6645MFX is RoHS non-compliant. Both parts maintain REACH Unaffected status. Organizations subject to RoHS directives must use the LMH6645MFX/NOPB variant.

Frequently Asked Questions (FAQ)

Q: Are the LMH6645MFX and LMH6645MFX/NOPB electrically identical?

A: Yes. Both parts are voltage feedback operational amplifiers with identical electrical specifications: 22V/µs slew rate, 55 MHz bandwidth, 650 nA input bias current, 1 mV input offset voltage, 725 µA supply current, and 20 mA output current per channel. They operate across the same 2.5V to 12V supply range and -40°C to 85°C temperature range.

Q: What is the difference between these two part numbers?

A: The primary differences are product status and regulatory compliance. The LMH6645MFX is obsolete and RoHS non-compliant. The LMH6645MFX/NOPB is active and RoHS3 compliant. The "/NOPB" suffix indicates lead-free, RoHS-compliant packaging.

Q: Can I use LMH6645MFX/NOPB as a direct replacement for LMH6645MFX?

A: Yes. The LMH6645MFX/NOPB is a direct pin-for-pin and functionally equivalent replacement. No circuit modifications are required. The SOT-23-5 package footprint is identical.

Q: Are there any packaging differences?

A: Both parts use the same SC-74A / SOT-753 surface mount package (SOT-23-5 supplier device package). Packaging format differs: LMH6645MFX is supplied in standard packaging, while LMH6645MFX/NOPB is available in Cut Tape (CT) and Digi-Reel® formats.

Q: Which part should I specify for new production?

A: Specify LMH6645MFX/NOPB for all new designs and production. This part is active, RoHS3 compliant, and has significantly higher inventory availability (45,200 pcs versus 2,459 pcs for the obsolete variant).

Q: Is the moisture sensitivity level the same?

A: Yes. Both parts have MSL 1 (Unlimited), indicating no moisture sensitivity restrictions for storage or handling.

Q: What is the operating temperature range for both parts?

A: Both parts operate from -40°C to 85°C, suitable for industrial and commercial temperature environments.