LM2679T-3.3 Equivalent & Substitute Parts

Part Overview

The LM2679T-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 and 5A current capacity. The device operates across an input voltage range of 8V to 40V and is housed in a TO-220-7 package with formed leads for through-hole mounting.

The LM2679T-3.3 carries an obsolete product status. Identifying equivalent substitute parts is necessary to ensure design continuity, maintain supply chain reliability, and support ongoing production or maintenance requirements for systems utilizing this regulator.

Substiute Parts

LM2679T-3.3

Texas InstrumentsIn Stock: 2172LM2679T-3.3 Datasheet

Current PartRFQ

LM2679T-3.3/NOPB

Texas InstrumentsIn Stock: 1033LM2679T-3.3/NOPB Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the LM2679T-3.3 is determined by strict equivalence across the following electrical and mechanical parameters:

• Output voltage specification: 3.3V fixed
• Output current rating: 5A minimum
• Input voltage operating range: 8V to 40V
• Switching topology: Buck converter
• Package configuration: TO-220-7 Formed Leads
• Mounting method: Through Hole
• Operating temperature range: -40°C to 125°C

The LM2679T-3.3/NOPB qualifies as a direct substitute based on identical electrical specifications and package configuration. The primary distinction between the main part and its substitute is product status and compliance certification.

Parameter Comparison

Engineering Selection Recommendations

The LM2679T-3.3/NOPB is the direct equivalent substitute for the obsolete LM2679T-3.3. Both parts share identical electrical and mechanical specifications, ensuring functional compatibility in existing designs without circuit modification.

The LM2679T-3.3/NOPB carries an active product status, providing assured long-term availability and supply chain continuity. Additionally, the substitute part meets ROHS3 compliance requirements, whereas the original part is RoHS non-compliant. For applications subject to environmental or regulatory compliance mandates, the LM2679T-3.3/NOPB is the appropriate selection.

Both parts maintain REACH Unaffected status and carry identical ECCN and HTSUS classifications, confirming regulatory equivalence for export and trade purposes.

Frequently Asked Questions (FAQ)

Q: Can the LM2679T-3.3/NOPB be used as a direct replacement for the LM2679T-3.3?

A: Yes. The LM2679T-3.3/NOPB is electrically and mechanically identical to the LM2679T-3.3. All electrical parameters, output specifications, input voltage range, switching frequency, and package configuration are equivalent. No circuit redesign is required.

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

A: The "/NOPB" designation indicates "No Plumbum" (lead-free) construction and is associated with RoHS3 compliance. This suffix distinguishes the part from earlier versions that may contain lead-based solder or finishes.

Q: Why is the original LM2679T-3.3 marked as obsolete?

A: Product obsolescence typically results from manufacturer discontinuation decisions. The availability of the active LM2679T-3.3/NOPB substitute ensures that designs can transition to a supported, compliant alternative without functional impact.

Q: Are there any thermal or performance differences between the two parts?

A: No. Both parts operate across the same temperature range (-40°C to 125°C junction temperature) and deliver identical switching frequency (260kHz) and current output (5A). Thermal performance and efficiency characteristics are equivalent.

Q: Is the TO-220-7 package configuration identical for both parts?

A: Yes. Both the LM2679T-3.3 and LM2679T-3.3/NOPB use the TO-220-7 Formed Leads package with through-hole mounting. PCB layout and thermal management considerations remain unchanged.

Q: What compliance certifications differ between the two parts?

A: The primary compliance difference is RoHS status. The LM2679T-3.3/NOPB is ROHS3 compliant, while the original LM2679T-3.3 is RoHS non-compliant. Both maintain REACH Unaffected status and identical export classifications (ECCN: EAR99; HTSUS: 8542.39.0001).