LM317LDR2 Equivalent & Substitute Parts

Part Overview

The LM317LDR2 is a linear voltage regulator IC from onsemi designed for positive adjustable output applications. This Surface Mount device delivers 100mA output current with adjustable voltage regulation from 1.2V to 37V, suitable for power management applications requiring precision voltage control. The LM317LDR2 is classified as Obsolete, making equivalent substitute parts necessary for ongoing production and maintenance applications. Substitute parts maintain the same functional specifications while offering improved availability and compliance status.

Substiute Parts

LM317LDR2

onsemiIn Stock: 3645LM317LDR2 Datasheet

Current PartRFQ

LM317LDR2G

onsemiIn Stock: 980453LM317LDR2G Datasheet

DirectRFQ

LM217LD13TR

STMicroelectronicsIn Stock: 40567LM217LD13TR Datasheet

SimilarRFQ

LM317LCDR

Texas InstrumentsIn Stock: 2782LM317LCDR Datasheet

SimilarRFQ

LM317LD13TR

STMicroelectronicsIn Stock: 886604LM317LD13TR Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the LM317LDR2 are classified based on electrical and mechanical compatibility within the LM317 regulator family. All substitute candidates maintain identical or equivalent performance across the following critical parameters: positive adjustable output configuration, 100mA output current capability, 8-SOIC package form factor, and core protection features (Over Current, Over Temperature, Short Circuit).

Substitution logic is determined by:

• Output voltage range compatibility (1.2V to 37V minimum requirement)
• Maximum input voltage rating (40V or higher)
• Output current rating (100mA minimum)
• Package compatibility (8-SOIC form factor)
• Operating temperature range overlap (0°C ~ 125°C minimum)
• Surface Mount mounting type

Parts are grouped as Direct Manufacturer Equivalent, Similar Manufacturer, and Parametric Equivalent based on specification alignment and product status.

Parameter Comparison

Engineering Selection Recommendations

LM317LDR2G (onsemi) is the primary direct equivalent substitute. This part maintains identical electrical specifications and 8-SOIC packaging while offering Active product status and ROHS3 compliance. Inventory availability is significantly higher at 980,400 units.

LM317LD13TR (STMicroelectronics) is a parametric equivalent offering full electrical compatibility with identical voltage ratings (40V input, 37V output maximum) and 100mA output current. This part provides Active status, ROHS3 compliance, and the highest inventory availability at 886,524 units. Quiescent current is 5mA versus the original 10mA specification.

LM317LCDR (Texas Instruments) is a similar manufacturer alternative with Active status and ROHS3 compliance. This part has a reduced maximum output voltage of 32V and maximum input voltage of 38V, making it suitable only for applications not requiring the full 37V output range. Quiescent current is lower at 2.5mA.

LM217LD13TR (STMicroelectronics) is a similar manufacturer part with extended operating temperature range (-40°C ~ 125°C). This part omits Over Current protection, retaining only Over Temperature and Short Circuit protection. Use is limited to applications where Over Current protection is not required.

For new designs and production requiring full specification compliance with improved availability and regulatory compliance, LM317LDR2G or LM317LD13TR are recommended. For applications with reduced voltage output requirements, LM317LCDR is acceptable.

Frequently Asked Questions (FAQ)

Q: Can LM317LDR2G directly replace LM317LDR2 in existing designs?

A: Yes. LM317LDR2G maintains identical electrical specifications, output voltage range (1.2V to 37V), output current (100mA), and 8-SOIC package form factor. The primary difference is product status (Active versus Obsolete) and improved RoHS compliance.

Q: What is the difference between LM317LD13TR and LM317LDR2?

A: Both parts share identical voltage ratings (40V input maximum, 37V output maximum) and 100mA output current. LM317LD13TR has lower quiescent current (5mA versus 10mA) and is manufactured by STMicroelectronics. Both use the same 8-SOIC package and offer equivalent electrical performance.

Q: Why does LM317LCDR have a lower maximum output voltage (32V)?

A: LM317LCDR is specified with a 32V maximum output voltage by Texas Instruments, compared to 37V for other LM317 variants. This represents a design or specification difference by the manufacturer. Applications requiring output voltages above 32V must use alternative parts.

Q: Is LM217LD13TR compatible with all LM317LDR2 applications?

A: LM217LD13TR is compatible for applications not requiring Over Current protection. This part lacks the Over Current protection feature present in LM317LDR2, retaining only Over Temperature and Short Circuit protection. Verify application requirements before substitution.

Q: Are all substitute parts available in the same packaging?

A: Yes. All substitute parts use the 8-SOIC (0.154", 3.90mm Width) Surface Mount package, ensuring mechanical and electrical compatibility with existing PCB layouts and assembly processes.

Q: What is the impact of different quiescent current specifications?

A: Quiescent current (Iq) represents standby power consumption. LM317LCDR has the lowest at 2.5mA, while LM317LDR2 and LM317LDR2G specify 10mA. LM317LD13TR specifies 5mA. Lower quiescent current reduces power dissipation in standby conditions. Select based on application power budget requirements.

Q: Do all substitute parts meet RoHS compliance requirements?

A: LM317LDR2 is RoHS non-compliant. All substitute parts (LM317LDR2G, LM217LD13TR, LM317LCDR, LM317LD13TR) are ROHS3 compliant, meeting current regulatory requirements for new production.