LM2585T-3.3 Equivalent & Substitute Parts

Part Overview

The LM2585T-3.3 is a boost, flyback, and forward converter switching regulator IC from Texas Instruments, configured to deliver a fixed 3.3V output at 3A (switch current) in a TO-220-5 package. This component operates across a wide input voltage range of 4V to 40V with a switching frequency of 100kHz, making it suitable for multiple power conversion topologies in industrial and embedded applications.

The main part number LM2585T-3.3 carries an obsolete product status. Identifying equivalent and substitute parts is necessary to ensure design continuity, maintain supply chain reliability, and support long-term product availability for existing applications and legacy system maintenance.

Substiute Parts

LM2585T-3.3

Texas InstrumentsIn Stock: 2116LM2585T-3.3 Datasheet

Current PartRFQ

LM2585T-3.3/NOPB

National SemiconductorIn Stock: 957LM2585T-3.3/NOPB Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the LM2585T-3.3 is determined by strict equivalence across the following critical parameters:

• Fixed output voltage of 3.3V
• Output current capability of 3A (switch)
• Input voltage range of 4V to 40V
• Switching frequency of 100kHz
• Support for boost, flyback, and forward converter topologies
• Positive fixed output configuration
• Operating temperature range of -40°C to 125°C
• TO-220-5 package with through-hole mounting
• Absence of synchronous rectifier functionality

Parts meeting all these specifications are classified as direct equivalents. The LM2585T-3.3/NOPB variant qualifies as a direct substitute based on identical electrical and mechanical parameters.

Parameter Comparison

Engineering Selection Recommendations

The LM2585T-3.3/NOPB is a direct functional equivalent to the LM2585T-3.3. Both parts share identical electrical specifications, package configuration, and operational parameters. The primary distinction is product status: the original LM2585T-3.3 is obsolete, while the LM2585T-3.3/NOPB maintains active status with current manufacturing support.

For new designs and ongoing production requiring this switching regulator topology, the LM2585T-3.3/NOPB is the appropriate selection. Both parts carry identical export classification (EAR99) and tariff codes (8542.39.0001), ensuring regulatory consistency. The /NOPB suffix indicates lead-free plating, aligning with modern manufacturing standards.

Frequently Asked Questions (FAQ)

Q: Can the LM2585T-3.3/NOPB be used as a direct replacement for the LM2585T-3.3?

A: Yes. Both parts deliver identical electrical performance across all specified parameters: 3.3V fixed output, 3A switch current, 4V to 40V input range, 100kHz switching frequency, and -40°C to 125°C operating temperature. The TO-220-5 package and through-hole mounting are identical, enabling direct PCB substitution without circuit modification.

Q: What does the /NOPB suffix indicate?

A: The /NOPB designation specifies lead-free plating on the component leads, meeting modern environmental and manufacturing requirements. This does not affect electrical performance or functional compatibility.

Q: Are there differences in RoHS compliance between these parts?

A: The LM2585T-3.3 is listed as RoHS non-compliant. The LM2585T-3.3/NOPB, with its lead-free plating, aligns with RoHS directives. Applications subject to RoHS requirements should use the /NOPB variant.

Q: Can these parts be used interchangeably in boost, flyback, and forward converter topologies?

A: Yes. Both parts support all three topologies with identical specifications. Circuit design and application requirements remain unchanged when substituting between these parts.

Q: What is the significance of the TO-220-5 package?

A: The TO-220-5 package is a through-hole component with five leads, providing robust mechanical connection and thermal management through the mounting pad. This package type is standard for power management ICs in this current and voltage class and ensures compatibility with existing PCB designs.