LMS1587CSX-3.3 Linear Voltage Regulator - Equivalent & Substitute Parts

Part Overview

The LMS1587CSX-3.3 is a linear voltage regulator IC from Texas Instruments, delivering a fixed 3.3V output at 3A in a TO-263 (DDPAK-3) surface mount package. This part is classified as "Not For New Designs," indicating it has been superseded. Finding equivalent or substitute parts is necessary for ongoing production support, maintenance applications, or when the primary part becomes unavailable. The substitute parts listed maintain electrical and mechanical compatibility while offering improved product status and compliance certifications.

Substiute Parts

LMS1587CSX-3.3

Texas InstrumentsIn Stock: 2662LMS1587CSX-3.3 Datasheet

Current PartRFQ

LMS1587CSX-3.3/NOPB

Texas InstrumentsIn Stock: 1332LMS1587CSX-3.3/NOPB Datasheet

DirectRFQ

LT1117CM-3.3#PBF

Analog Devices Inc.In Stock: 2056LT1117CM-3.3#PBF Datasheet

MFR RecommendedRFQ

LT1117CM-3.3#TRPBF

Analog Devices Inc.In Stock: 1894LT1117CM-3.3#TRPBF Datasheet

MFR RecommendedRFQ

LT1587CM-3.3#PBF

Analog Devices Inc.In Stock: 1120LT1587CM-3.3#PBF Datasheet

MFR RecommendedRFQ

LT1587CM-3.3#TRPBF

Analog Devices Inc.In Stock: 1683LT1587CM-3.3#TRPBF Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility is determined by the following criteria:

Primary Compatibility Parameters:

• Fixed output voltage of 3.3V
• Output current capability of 3A or greater
• TO-263 (DDPAK-3) package configuration
• Surface mount mounting type
• Operating temperature range of 0°C to 125°C

Substitution Categories:

Category 1: Direct Packaging Variant LMS1587CSX-3.3/NOPB is a direct substitute from Texas Instruments, identical to the main part but with active product status and RoHS3 compliance. This part differs only in packaging designation (NOPB vs. standard) and compliance certifications.

Category 2: Reduced Current Output (800mA) LT1117CM-3.3#PBF and LT1117CM-3.3#TRPBF from Analog Devices are suitable substitutes where the application requires 800mA or less. These parts maintain the 3.3V fixed output and TO-263 package but deliver lower maximum current. The higher input voltage rating (15V vs. 13V) and improved PSRR (75dB vs. 72dB) provide additional design margin.

Category 3: Full Current Output (3A) LT1587CM-3.3#PBF and LT1587CM-3.3#TRPBF from Analog Devices are direct functional equivalents, delivering 3A output current with identical voltage dropout characteristics. These parts differ in input voltage rating (7V vs. 13V) and include short circuit protection in addition to over current and over temperature protection.

Parameter Comparison

Engineering Selection Recommendations

For Direct Replacement (Preferred): Select LMS1587CSX-3.3/NOPB when the application requires an exact functional equivalent with improved compliance. This part maintains all electrical specifications of the original while offering active product status and RoHS3 compliance, eliminating the obsolescence risk of the "Not For New Designs" designation.

For Current-Limited Applications (800mA or Less): The LT1117CM-3.3 series (available in both tube and tape & reel packaging) is suitable when the application draws 800mA or less. These parts provide superior input voltage rating (15V) and PSRR performance (75dB), offering additional design margin for noise-sensitive applications. Both packaging variants are RoHS3 compliant and carry active product status.

For Full 3A Current Requirement: The LT1587CM-3.3 series from Analog Devices delivers the full 3A output current with identical voltage dropout characteristics. These parts include short circuit protection in addition to standard over current and over temperature protection. Note the reduced maximum input voltage (7V vs. 13V) when evaluating circuit design margins. Both tube and tape & reel packaging options are available with RoHS3 compliance and active product status.

Compliance Consideration: All substitute parts carry RoHS3 compliance and active product status, addressing the obsolescence and regulatory concerns of the original LMS1587CSX-3.3 designation.

Frequently Asked Questions (FAQ)

Q: Can LT1117CM-3.3 substitute for LMS1587CSX-3.3 in all applications? A: LT1117CM-3.3 is suitable only for applications requiring 800mA or less output current. The LMS1587CSX-3.3 is rated for 3A. For full 3A applications, use LT1587CM-3.3 instead.

Q: What is the difference between LT1117CM-3.3#PBF and LT1117CM-3.3#TRPBF? A: Both parts are electrically identical. The difference is packaging: #PBF indicates tube packaging, while #TRPBF indicates tape & reel packaging. Select based on your assembly process requirements.

Q: Why does LT1587CM-3.3 have a lower maximum input voltage (7V) compared to the original (13V)? A: This is a specification difference between the Analog Devices LT1587 and Texas Instruments LMS1587 designs. Verify your input voltage does not exceed 7V when using LT1587CM-3.3 variants.

Q: Are all substitute parts RoHS compliant? A: Yes. All listed substitute parts carry RoHS3 compliance. The original LMS1587CSX-3.3 is RoHS non-compliant.

Q: What additional protection does LT1587CM-3.3 provide? A: LT1587CM-3.3 includes short circuit protection in addition to over current and over temperature protection. The original LMS1587CSX-3.3 includes only over current and over temperature protection.

Q: Can I use LMS1587CSX-3.3/NOPB as a drop-in replacement? A: Yes. LMS1587CSX-3.3/NOPB is a direct equivalent with identical electrical specifications, package, and pinout. The only differences are improved product status (Active vs. Not For New Designs) and RoHS3 compliance.

Q: Which substitute should I choose for new designs? A: For new designs requiring 3A output, use LT1587CM-3.3#TRPBF (tape & reel packaging is standard for production). For 800mA applications, use LT1117CM-3.3#TRPBF. Both are actively supported by Analog Devices with RoHS3 compliance.