LM3670MF-1.8 Equivalent & Substitute Parts

Part Overview

The LM3670MF-1.8 is a buck switching regulator IC from Texas Instruments designed for positive fixed 1.8V output applications. This device delivers 350mA output current with a 1MHz switching frequency and integrated synchronous rectification. The part is classified as obsolete, making equivalent substitutes necessary for ongoing production and maintenance applications. Direct alternatives maintain identical electrical specifications and package compatibility while offering improved availability and active product status.

Substiute Parts

LM3670MF-1.8

Texas InstrumentsIn Stock: 8563LM3670MF-1.8 Datasheet

Current PartRFQ

LM3670MF-1.8/NOPB

National SemiconductorIn Stock: 1796LM3670MF-1.8/NOPB Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the LM3670MF-1.8 is determined by strict equivalence across the following critical parameters:

• Output voltage specification: 1.8V fixed
• Output current capability: 350mA minimum
• Input voltage operating range: 2.5V to 5.5V
• Switching topology: Buck converter with synchronous rectification
• Package form factor: SC-74A, SOT-753 (SOT-23-5)
• Operating temperature range: -40°C to 85°C
• Switching frequency: 1MHz

The LM3670MF-1.8/NOPB qualifies as a direct substitute based on complete parameter alignment across all electrical and mechanical specifications. The "/NOPB" suffix indicates lead-free (Pb-free) termination, representing a manufacturing variant of the same base product (LM3670) with identical functional performance.

Parameter Comparison

Engineering Selection Recommendations

The LM3670MF-1.8/NOPB is the direct equivalent for the obsolete LM3670MF-1.8. Selection between these parts should be based on the following factors:

Product Status: The LM3670MF-1.8 is classified as obsolete, while the LM3670MF-1.8/NOPB maintains active product status. For new designs and ongoing production, the active variant ensures long-term supply chain stability and manufacturer support.

Compliance and Certifications: Both parts share identical ECCN (EAR99) and HTSUS (8542.39.0001) classifications. The "/NOPB" designation indicates lead-free termination, which may align with specific procurement or environmental requirements depending on application context.

Electrical and Mechanical Compatibility: Complete parameter equivalence across input voltage range, output specifications, switching characteristics, package form factor, and operating temperature range ensures direct pin-for-pin and functional compatibility in existing circuit designs.

Inventory Considerations: The LM3670MF-1.8 shows 8460 units in stock (obsolete status), while the LM3670MF-1.8/NOPB shows 1698 units in stock (active status). Availability decisions should account for immediate versus long-term supply requirements.

Frequently Asked Questions (FAQ)

Q: Can the LM3670MF-1.8/NOPB be used as a direct replacement for the LM3670MF-1.8?

A: Yes. Both parts are functionally and electrically identical across all specified parameters. They share the same output voltage (1.8V), output current (350mA), input voltage range (2.5V to 5.5V), switching frequency (1MHz), package type (SC-74A, SOT-753), and operating temperature range (-40°C to 85°C). Pin-for-pin and circuit-level compatibility is complete.

Q: What does the "/NOPB" suffix indicate?

A: The "/NOPB" suffix designates a lead-free (Pb-free) termination variant. This represents a manufacturing specification change rather than a functional or electrical modification. The part maintains identical performance characteristics to the non-suffixed version.

Q: Why is the LM3670MF-1.8 classified as obsolete?

A: Obsolete status indicates the manufacturer has discontinued active production and support for this specific part number. The LM3670MF-1.8/NOPB remains in active production, making it the recommended choice for new applications and ongoing production requirements.

Q: Are there any differences in operating temperature range between these parts?

A: No. Both parts operate across the identical temperature range of -40°C to 85°C (TA).

Q: Do both parts support synchronous rectification?

A: Yes. Both the LM3670MF-1.8 and LM3670MF-1.8/NOPB include integrated synchronous rectification, enabling efficient buck conversion at the specified 1MHz switching frequency.

Q: What is the moisture sensitivity level for the LM3670MF-1.8/NOPB?

A: The moisture sensitivity level is not specified in the provided data for the LM3670MF-1.8/NOPB. The LM3670MF-1.8 is rated MSL 1 (Unlimited), indicating minimal moisture sensitivity. For specific MSL requirements, consult the manufacturer's datasheet.

Q: Are both parts RoHS compliant?

A: Both parts are classified as RoHS non-compliant based on the provided specifications.

Q: Can these parts be used interchangeably in existing PCB designs?

A: Yes. Identical package type (SC-74A, SOT-753), pin configuration, and electrical specifications ensure complete interchangeability in existing circuit designs without layout or schematic modifications.