LM2673SD-3.3 Equivalent & Substitute Parts

Part Overview

The LM2673SD-3.3 is a buck switching regulator IC from Texas Instruments, part of the SIMPLE SWITCHER® series. It delivers a fixed 3.3V output at 3A from an 8V to 40V input, operating across the industrial temperature range of -40°C to 125°C. The device is classified as obsolete, making identification of suitable alternatives essential for ongoing production support and design continuity.

Substiute Parts

LM2673SD-3.3

Texas InstrumentsIn Stock: 846LM2673SD-3.3 Datasheet

Current PartRFQ

LM2673SD-3.3/NOPB

National SemiconductorIn Stock: 2329LM2673SD-3.3/NOPB Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the LM2673SD-3.3 is determined by strict equivalence across the following electrical and mechanical parameters:

• Output voltage configuration (3.3V fixed)
• Output current capability (3A minimum)
• Input voltage operating range (8V to 40V)
• Switching topology (buck converter)
• Package form factor (14-VDFN Exposed Pad)
• Thermal operating range (-40°C to 125°C)
• Synchronous rectifier configuration (non-synchronous)

The LM2673SD-3.3/NOPB qualifies as a direct substitute based on identical electrical specifications and package compatibility.

Parameter Comparison

Engineering Selection Recommendations

The LM2673SD-3.3/NOPB is the qualified substitute for the obsolete LM2673SD-3.3. Both devices share identical electrical specifications and package geometry, ensuring direct functional equivalence.

The primary distinction is product status: the LM2673SD-3.3/NOPB is active and available, while the original part is obsolete. Additionally, the substitute meets RoHS3 compliance requirements, whereas the original does not. For new designs or production continuity, the LM2673SD-3.3/NOPB is the appropriate selection.

Both parts maintain REACH Unaffected status and EAR99 export classification.

Frequently Asked Questions (FAQ)

Q: Can the LM2673SD-3.3/NOPB replace the LM2673SD-3.3 in existing designs?

A: Yes. Both devices are electrically and mechanically identical across all specified parameters, including output voltage, current rating, input range, switching frequency, and package form factor. Direct substitution is supported.

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

A: The "/NOPB" designation indicates the part is supplied in bulk packaging without lead-free plating. This is a packaging and distribution designation that does not affect electrical performance or compatibility.

Q: Are there package compatibility concerns?

A: No. Both parts use the 14-VDFN Exposed Pad package with identical pinout and thermal characteristics. PCB layout and thermal management designs require no modification.

Q: Why is RoHS compliance different between the two parts?

A: The original LM2673SD-3.3 predates RoHS3 requirements and is non-compliant. The LM2673SD-3.3/NOPB was manufactured to current RoHS3 standards. For applications subject to RoHS regulations, the substitute is the required choice.

Q: Is the operating temperature range identical?

A: Yes. Both devices operate across -40°C to 125°C junction temperature, supporting industrial and extended temperature applications without derating.