LM317LDG Linear Voltage Regulator IC Equivalent & Substitute Parts

Part Overview

The LM317LDG is a positive adjustable linear voltage regulator IC manufactured by onsemi, designed for applications requiring adjustable output voltage from 1.2V to 37V at 100mA output current. The device is packaged in 8-SOIC surface mount configuration and includes integrated protection features for over-current, over-temperature, and short-circuit conditions.

The LM317LDG is classified as obsolete product status. Identifying equivalent and substitute parts is necessary to ensure design continuity, maintain supply chain reliability, and support ongoing production requirements for applications currently utilizing this component.

Substiute Parts

LM317LDG

onsemiIn Stock: 5740LM317LDG Datasheet

Current PartRFQ

LM317LDR2G

onsemiIn Stock: 980453LM317LDR2G Datasheet

DirectRFQ

LM317LD13TR

STMicroelectronicsIn Stock: 886604LM317LD13TR Datasheet

DirectRFQ

LM217LD13TR

STMicroelectronicsIn Stock: 40567LM217LD13TR Datasheet

SimilarRFQ

LM317LCD

Texas InstrumentsIn Stock: 3486LM317LCD Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the LM317LDG are identified based on strict electrical and mechanical parameter equivalence within the LM317 regulator family. The substitution logic is based on the following critical parameters:

• Package compatibility: All substitutes must use 8-SOIC surface mount package with identical 0.154" (3.90mm) width
• Output voltage range: Minimum 1.2V to maximum output voltage of 37V or greater
• Output current: 100mA minimum capability
• Input voltage rating: 40V maximum input voltage
• Protection features: Over-current, over-temperature, and short-circuit protection
• Operating temperature range: 0°C to 125°C minimum
• RoHS3 compliance: All substitutes must maintain ROHS3 compliance status

Parts are categorized as direct substitutes when all electrical parameters match within specification limits. Similar substitutes are identified when minor parameter variations exist but functional equivalence is maintained for standard applications.

Parameter Comparison

Engineering Selection Recommendations

LM317LDR2G (onsemi) is the primary direct substitute for LM317LDG. Both parts are manufactured by onsemi with identical electrical specifications and active product status for LM317LDR2G ensures ongoing availability and supply chain support. This part maintains all critical parameters including 40V maximum input voltage, 37V maximum output voltage, 100mA output current, and complete protection feature set. Packaging is identical 8-SOIC format. The LM317LDR2G is available in Cut Tape and Digi-Reel packaging options, providing flexibility for production requirements.

LM317LD13TR (STMicroelectronics) is a direct electrical substitute with active product status. All core electrical parameters match the LM317LDG specification. The quiescent current is lower at 5mA compared to 10mA, which may provide marginal power consumption benefits in battery-powered applications. PSRR specification shows a range of 80dB to 65dB rather than fixed 80dB. This part is suitable for applications where STMicroelectronics supply chain preference or qualification exists.

LM317LCD (Texas Instruments) is classified as a similar substitute due to reduced maximum input voltage (38V versus 40V) and reduced maximum output voltage (32V versus 37V). The quiescent current is significantly lower at 2.5mA. This part is suitable only for applications where the reduced voltage ratings do not exceed design requirements. Product status is Last Time Buy, indicating limited future availability.

LM217LD13TR (STMicroelectronics) is a similar substitute based on the LM217 base product number. This part maintains the same package, output current, and voltage output range but operates over an extended temperature range of -40°C to 125°C. Over-current protection is not specified for this variant. This part is suitable for applications requiring extended low-temperature operation where the LM217 specification is acceptable.

Frequently Asked Questions (FAQ)

Q: Can LM317LDR2G directly replace LM317LDG in existing designs?

A: Yes. LM317LDR2G is a direct substitute with identical electrical specifications, package format, and protection features. No circuit modifications are required. The primary difference is product status change from obsolete to active, ensuring continued supply availability.

Q: What is the key difference between LM317LD13TR and LM317LDG?

A: LM317LD13TR is manufactured by STMicroelectronics versus onsemi for LM317LDG. Electrical specifications are equivalent with the exception of quiescent current (5mA versus 10mA) and PSRR specification format. Both parts use identical 8-SOIC packaging and support the same output voltage range.

Q: Is LM317LCD suitable as a substitute for designs requiring 40V input voltage?

A: No. LM317LCD has a maximum input voltage rating of 38V, which is below the 40V specification of LM317LDG. This part is suitable only for applications where input voltage does not exceed 38V and output voltage does not exceed 32V.

Q: What is the difference between LM317 and LM217 base product numbers?

A: LM217LD13TR is based on the LM217 product line and operates over an extended temperature range of -40°C to 125°C compared to 0°C to 125°C for LM317 variants. Over-current protection is not specified for the LM217 variant. Selection between LM317 and LM217 depends on application temperature requirements and protection feature needs.

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

A: No. LM317LDR2G is available in Cut Tape and Digi-Reel packaging. LM317LD13TR and LM217LD13TR are available in Cut Tape and Digi-Reel packaging. LM317LCD is available in Tube packaging. Packaging selection should be coordinated with production assembly requirements and inventory management practices.

Q: Do all substitute parts maintain RoHS3 compliance?

A: Yes. All identified substitute parts maintain ROHS3 compliance status, ensuring compatibility with environmental and regulatory requirements equivalent to the original LM317LDG specification.