LM2677SX-3.3 Equivalent & Substitute Parts

Part Overview

The LM2677SX-3.3 is a buck switching regulator IC from Texas Instruments' SIMPLE SWITCHER® series, designed for step-down voltage conversion with a fixed 3.3V output at 5A maximum current. This device operates across an input voltage range of 8V to 40V with a switching frequency of 260kHz and is housed in a TO-263-8 (D2PAK) surface mount package.

The LM2677SX-3.3 carries an Obsolete product status. Identifying equivalent and substitute parts is necessary to ensure design continuity, maintain supply chain reliability, and support ongoing production requirements for applications currently utilizing this regulator.

Substiute Parts

LM2677SX-3.3

Texas InstrumentsIn Stock: 882LM2677SX-3.3 Datasheet

Current PartRFQ

LM2677SX-3.3/NOPB

Texas InstrumentsIn Stock: 867LM2677SX-3.3/NOPB Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the LM2677SX-3.3 is determined by strict equivalence across the following critical parameters:

• Output voltage configuration: Fixed 3.3V
• Output current capability: 5A minimum
• Input voltage operating range: 8V to 40V minimum
• Topology: Buck (step-down) switching regulator
• Package: TO-263-8 (D2PAK) surface mount
• Switching frequency: 260kHz
• Operating temperature range: -40°C to 125°C

Substitute parts must maintain identical electrical specifications and mechanical compatibility to ensure direct replacement without circuit redesign or PCB modification.

Parameter Comparison

Engineering Selection Recommendations

The LM2677SX-3.3/NOPB is the direct equivalent substitute for the obsolete LM2677SX-3.3. Both devices are manufactured by Texas Instruments and share identical electrical and mechanical specifications across all critical parameters: 3.3V fixed output, 5A current capability, 8V to 40V input range, 260kHz switching frequency, and TO-263-8 package configuration.

The primary distinction between these parts is product lifecycle status and regulatory compliance. The LM2677SX-3.3/NOPB carries Active product status, ensuring ongoing availability and manufacturer support. Additionally, the LM2677SX-3.3/NOPB is ROHS3 compliant and REACH affected, reflecting current environmental and regulatory standards, whereas the original LM2677SX-3.3 is RoHS non-compliant and REACH unaffected.

For new designs or production continuity, the LM2677SX-3.3/NOPB is the appropriate selection. The packaging format difference (Tape & Reel versus bulk) reflects standard distribution practices and does not affect electrical or mechanical compatibility.

Frequently Asked Questions (FAQ)

Q: Can the LM2677SX-3.3/NOPB be used as a direct replacement for the LM2677SX-3.3?

A: Yes. Both parts are electrically and mechanically identical. The LM2677SX-3.3/NOPB is the active equivalent with current product status and improved regulatory compliance.

Q: Are there any circuit design changes required when switching from LM2677SX-3.3 to LM2677SX-3.3/NOPB?

A: No. The devices share identical output voltage (3.3V), output current (5A), input voltage range (8V to 40V), switching frequency (260kHz), and package configuration (TO-263-8). No PCB modifications or external component adjustments are necessary.

Q: What is the significance of the "/NOPB" suffix?

A: The "/NOPB" designation indicates the part is supplied in Tape & Reel packaging format without plumbum (lead-free), reflecting RoHS3 compliance and modern manufacturing standards.

Q: Does the RoHS compliance difference affect functionality?

A: No. RoHS compliance is a regulatory and material composition specification. Electrical performance and functional characteristics remain identical between RoHS-compliant and non-compliant versions of the same device.

Q: Is the TO-263-8 package compatible with existing PCB layouts designed for the LM2677SX-3.3?

A: Yes. Both parts use the identical TO-263-8 (D2PAK, 7 Leads + Tab) surface mount package. PCB footprints, land patterns, and mounting requirements are fully compatible.