LL42-GS18 Equivalent & Substitute Parts

Part Overview

The LL42-GS18 is a Schottky rectifier diode manufactured by Vishay General Semiconductor - Diodes Division, rated for 30 V DC reverse voltage and 200 mA average rectified current in a surface mount SOD-80 MiniMELF package. This component is classified as Active product status with AEC-Q101 automotive qualification. Substitute parts are identified when equivalent electrical performance parameters and mechanical compatibility are required due to inventory constraints, manufacturing discontinuation, or design flexibility needs.

Substiute Parts

LL42-GS18

Vishay General Semiconductor - Diodes DivisionIn Stock: 976LL42-GS18 Datasheet

Current PartRFQ

TMMBAT42FILM

STMicroelectronicsIn Stock: 42789TMMBAT42FILM Datasheet

UpgradeRFQ

TMMBAT43FILM

STMicroelectronicsIn Stock: 23622TMMBAT43FILM Datasheet

UpgradeRFQ

BAS85,115

Nexperia USA Inc.In Stock: 235206BAS85,115 Datasheet

MFR RecommendedRFQ

BAS85,135

Nexperia USA Inc.In Stock: 4485BAS85,135 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the LL42-GS18 is determined by strict equivalence across the following critical parameters:

Electrical Equivalence Criteria:

• Voltage - DC Reverse (Vr) (Max): 30 V
• Current - Average Rectified (Io): 200 mA
• Technology: Schottky
• Speed Classification: Small Signal ≤ 200 mA (Io), Any Speed
• Reverse Recovery Time (trr): 5 ns

Mechanical Compatibility Criteria:

• Mounting Type: Surface Mount
• Package / Case: DO-213AC, MINI-MELF, SOD-80 or equivalent Mini MELF variants

Compliance Criteria:

• RoHS Status: ROHS3 Compliant
• Moisture Sensitivity Level (MSL): 1 (Unlimited)
• REACH Status: REACH Unaffected

Substitute parts are grouped into two categories: Upgrade Substitutes (STMicroelectronics TMMBAT series) and Manufacturer Recommended Substitutes (Nexperia BAS85 series). All identified substitutes maintain the core electrical specifications and surface mount package compatibility required for direct circuit board replacement.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitutes (STMicroelectronics TMMBAT Series):

TMMBAT42FILM and TMMBAT43FILM are direct electrical equivalents to the LL42-GS18 with identical reverse voltage (30 V), rectified current (200 mA), reverse recovery time (5 ns), reverse leakage current (500 nA @ 25 V), and junction capacitance (7 pF @ 1V, 1MHz). Both parts are Active product status with ROHS3 compliance and MSL 1 rating. The STMicroelectronics parts feature an extended operating temperature range (-65°C ~ 125°C) compared to the LL42-GS18 maximum of 125°C. Package designation is DO-213AA (Glass) Mini MELF, which is mechanically compatible with the SOD-80 MiniMELF footprint. These substitutes are available in Cut Tape (CT) & Digi-Reel® packaging with significantly higher inventory levels (42,700 and 23,600 units respectively).

Secondary Substitutes (Nexperia BAS85 Series):

BAS85,115 and BAS85,135 are manufacturer-recommended alternatives with identical reverse voltage (30 V) and rectified current (200 mA) specifications. Both maintain ROHS3 compliance and MSL 1 rating. The BAS85 series exhibits higher reverse leakage current (2.3 µA @ 25 V versus 500 nA @ 25 V) and slightly increased junction capacitance (10 pF @ 1V, 1MHz versus 7 pF). Forward voltage is specified at 800 mV @ 100 mA. BAS85,115 is packaged in Cut Tape (CT) & Digi-Reel® with 235,100 units in stock, while BAS85,135 is supplied in Tape & Reel (TR) with 4,390 units available. Both maintain the DO-213AC, MINI-MELF, SOD-80 package designation matching the original LL42-GS18.

Selection Basis:

All substitute parts maintain Active product status and full ROHS3 compliance. The choice between STMicroelectronics and Nexperia substitutes depends on specific application requirements regarding reverse leakage current tolerance and operating temperature range. The Nexperia BAS85 series provides identical package compatibility with the original LL42-GS18, while the STMicroelectronics TMMBAT series offers superior reverse leakage characteristics and extended temperature operation.

Frequently Asked Questions (FAQ)

Q: Can TMMBAT42FILM or TMMBAT43FILM be used as direct replacements for LL42-GS18 on existing circuit boards?

A: TMMBAT42FILM and TMMBAT43FILM are electrically equivalent to LL42-GS18 across all critical parameters (30 V reverse voltage, 200 mA current, 5 ns reverse recovery time, 500 nA reverse leakage). Both are surface mount devices in Mini MELF package format (DO-213AA Glass), which is mechanically compatible with the SOD-80 MiniMELF footprint of the LL42-GS18. Direct board-level substitution is supported.

Q: What is the difference between the STMicroelectronics TMMBAT42FILM and TMMBAT43FILM substitutes?

A: Both TMMBAT42FILM and TMMBAT43FILM share identical electrical specifications and package format. The distinction between TMMBAT42 and TMMBAT43 base product numbers reflects manufacturer part family designation. For the LL42-GS18 substitution application, both parts are functionally equivalent.

Q: Why do the Nexperia BAS85,115 and BAS85,135 parts show higher reverse leakage current (2.3 µA) compared to the LL42-GS18 (500 nA)?

A: The BAS85 series exhibits higher reverse leakage current specification (2.3 µA @ 25 V) relative to the LL42-GS18 and STMicroelectronics alternatives (500 nA @ 25 V). This parameter difference is provided in the manufacturer datasheets. Applications sensitive to reverse leakage current performance should account for this specification variance when selecting between substitute options.

Q: Are there package compatibility concerns between LL42-GS18 (SOD-80 MiniMELF) and the substitute parts?

A: The Nexperia BAS85,115 and BAS85,135 maintain identical package designation (DO-213AC, MINI-MELF, SOD-80) as the LL42-GS18, ensuring direct footprint compatibility. The STMicroelectronics TMMBAT42FILM and TMMBAT43FILM use DO-213AA (Glass) Mini MELF package format, which is mechanically compatible with SOD-80 MiniMELF footprints on standard circuit boards.

Q: What is the significance of the extended operating temperature range (-65°C ~ 125°C) offered by TMMBAT42FILM and TMMBAT43FILM?

A: The STMicroelectronics TMMBAT series specifies an operating temperature range of -65°C to 125°C, while the LL42-GS18 specifies a maximum junction temperature of 125°C. The extended lower temperature limit provides additional operational margin in cold environment applications. This specification difference does not affect substitution validity for applications operating within the LL42-GS18 temperature envelope.

Q: Are all substitute parts RoHS3 compliant and MSL 1 rated?

A: All identified substitute parts (TMMBAT42FILM, TMMBAT43FILM, BAS85,115, and BAS85,135) are ROHS3 compliant and carry MSL 1 (Unlimited) moisture sensitivity rating, matching the LL42-GS18 compliance profile.

Q: Which substitute part offers the highest inventory availability?

A: BAS85,115 (Nexperia) provides the highest inventory level at 235,100 units in stock, followed by TMMBAT42FILM (STMicroelectronics) at 42,700 units and TMMBAT43FILM (STMicroelectronics) at 23,600 units.