LM317LCD Equivalent & Substitute Parts

Part Overview

The LM317LCD is a linear voltage regulator IC from Texas Instruments designed for positive adjustable output applications. It delivers 100mA output current with an adjustable voltage range from 1.2V to 32V, making it suitable for general-purpose power management circuits requiring regulated DC voltage supplies.

The LM317LCD is currently in Last Time Buy status, indicating that Texas Instruments has discontinued or is phasing out this specific packaging variant. This necessitates identifying functionally equivalent substitute parts to ensure design continuity and procurement availability for new production runs or maintenance applications.

Substiute Parts

LM317LCD

Texas InstrumentsIn Stock: 3486LM317LCD Datasheet

Current PartRFQ

LM317LCDR

Texas InstrumentsIn Stock: 2782LM317LCDR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the LM317LCD is determined by strict equivalence across the following critical parameters:

• Output Configuration & Type: Must be Positive Adjustable
• Voltage Specifications: Input (Max) 38V, Output range 1.2V to 32V
• Current Rating: 100mA output capability
• Package Type: 8-SOIC surface mount package with 0.154" (3.90mm) width
• Electrical Performance: Quiescent current 2.5mA, PSRR 80dB ~ 65dB (120Hz)
• Protection: Over Current, Over Temperature, Short Circuit protection
• Compliance: ROHS3 Compliant, REACH Unaffected, MSL Level 1

The LM317LCDR meets all these criteria and is the manufacturer-recommended substitute. The primary difference is packaging format: LM317LCD is supplied in Tube packaging, while LM317LCDR is supplied in Cut Tape (CT) & Digi-Reel® format. Both use identical die and electrical specifications.

Parameter Comparison

Engineering Selection Recommendations

The LM317LCDR is the direct functional equivalent of the LM317LCD and is the manufacturer-recommended substitute. Selection of LM317LCDR is appropriate for the following reasons:

• Product Status: LM317LCDR maintains Active status with Texas Instruments, ensuring long-term availability and supply chain stability, whereas LM317LCD is Last Time Buy.
• Electrical Equivalence: All electrical parameters, performance specifications, and protection features are identical between the two parts.
• Compliance Alignment: Both parts maintain identical RoHS3 Compliance, REACH Unaffected status, and MSL Level 1 rating, ensuring regulatory and environmental requirements are met.
• Package Compatibility: Both parts use the 8-SOIC surface mount package with identical pinout and mechanical dimensions, allowing direct PCB layout compatibility.
• Packaging Format: The only difference is supply format. LM317LCDR is supplied in Cut Tape (CT) & Digi-Reel® format, which is standard for high-volume production and automated assembly processes.

Frequently Asked Questions (FAQ)

Q: Can LM317LCDR be used as a direct replacement for LM317LCD in existing designs?

A: Yes. The LM317LCDR is electrically and mechanically identical to the LM317LCD. Both use the same 8-SOIC package with identical pinout, electrical specifications, and performance characteristics. No circuit modifications are required.

Q: What is the difference between Tube and Cut Tape (CT) & Digi-Reel® packaging?

A: Tube packaging supplies components in plastic tubes, typically used for lower-volume or manual assembly processes. Cut Tape (CT) & Digi-Reel® packaging supplies components on continuous tape wound on reels, optimized for automated pick-and-place assembly equipment. The components themselves are identical; only the supply format differs.

Q: Why is LM317LCD listed as Last Time Buy?

A: Last Time Buy status indicates that Texas Instruments has discontinued this specific packaging variant. Customers are advised to transition to the LM317LCDR, which is the active equivalent supplied in standard production packaging formats.

Q: Are there any electrical performance differences between LM317LCD and LM317LCDR?

A: No. Both parts have identical electrical specifications, including output voltage range (1.2V to 32V), output current (100mA), quiescent current (2.5mA), PSRR (80dB ~ 65dB at 120Hz), and protection features (Over Current, Over Temperature, Short Circuit).

Q: Will LM317LCDR work in automated assembly processes?

A: Yes. LM317LCDR is supplied in Cut Tape (CT) & Digi-Reel® format, which is the standard packaging for automated pick-and-place assembly equipment. This format is preferred for high-volume production.

Q: Are compliance certifications the same for both parts?

A: Yes. Both LM317LCD and LM317LCDR are ROHS3 Compliant, REACH Unaffected, and have MSL Level 1 (Unlimited) moisture sensitivity rating.