TSM4459CS RLG Equivalent & Substitute Parts

Part Overview

The TSM4459CS RLG is a P-Channel MOSFET rated for 30V drain-to-source voltage with 17A continuous drain current at 25°C. This device is designed for surface mount applications in the 8-SOP package configuration. The part is classified as obsolete, necessitating identification of active equivalent components to maintain design continuity and ensure long-term supply availability for new production and field replacements.

Substiute Parts

TSM4459CS RLG

Taiwan Semiconductor CorporationIn Stock: 15890TSM4459CS RLG Datasheet

Current PartRFQ

TSM085P03CS RLG

Taiwan Semiconductor CorporationIn Stock: 18179TSM085P03CS RLG Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the TSM4459CS RLG is determined by the following critical parameters:

Mandatory Matching Criteria:

• FET Type: P-Channel
• Drain to Source Voltage (Vdss): 30V minimum
• Package / Case: 8-SOIC (0.154", 3.90mm Width)
• Mounting Type: Surface Mount
• Operating Temperature Range: -55°C to 150°C (TJ)

Functional Compatibility Criteria:

• Continuous Drain Current (Id): Equal to or greater than 17A
• Rds On (Max): Equal to or lower than 5.2 mOhm @ specified conditions
• Vgs(th) (Max): Within ±20V gate voltage specification
• Gate Charge (Qg): Acceptable for driver circuit compatibility

The TSM085P03CS RLG qualifies as a direct substitute based on matching all mandatory criteria while providing enhanced electrical performance characteristics. This part maintains identical voltage rating, package geometry, and thermal operating range while offering superior current handling and reduced on-resistance.

Parameter Comparison

Engineering Selection Recommendations

Product Status Consideration: The TSM4459CS RLG is classified as obsolete. The TSM085P03CS RLG is classified as active, ensuring continued availability and manufacturing support. Selection of the active substitute part eliminates supply chain risk associated with end-of-life components.

Compliance and Certification: Both parts maintain ROHS3 compliance and REACH unaffected status, satisfying regulatory requirements for electronic component procurement. The substitute part carries MSL rating of 1 (Unlimited), providing superior moisture handling characteristics compared to the main part's MSL rating of 3 (168 Hours).

Electrical Performance: The TSM085P03CS RLG provides doubled continuous drain current capacity (34A versus 17A) and significantly increased power dissipation capability (14W versus 2.5W). These enhancements deliver improved thermal margin and current handling headroom for applications operating at or near the original part's rated limits.

Mechanical and Thermal Compatibility: Identical package geometry (8-SOIC, 0.154" width, 3.90mm) and mounting type (surface mount) ensure direct PCB compatibility without layout modifications. Matching operating temperature range (-55°C to 150°C TJ) maintains thermal design equivalence.

Frequently Asked Questions (FAQ)

Q: Can the TSM085P03CS RLG be used as a direct replacement for the TSM4459CS RLG in existing designs?

A: Yes. Both parts share identical voltage rating (30V Vdss), package configuration (8-SOIC), and operating temperature range (-55°C to 150°C TJ). The substitute part provides enhanced current and power dissipation capabilities, making it functionally compatible for all applications within the original part's specifications.

Q: What are the key differences between these two P-Channel MOSFETs?

A: The primary differences are continuous drain current (17A versus 34A), power dissipation (2.5W versus 14W), and on-resistance characteristics. The substitute part delivers superior performance across these parameters while maintaining identical voltage and package specifications.

Q: Does the higher gate charge of the TSM4459CS RLG affect driver circuit compatibility?

A: Gate charge differences (78.4 nC versus 56 nC) may affect switching speed and driver power requirements. Driver circuits rated for the original part's gate charge specification will operate within acceptable parameters with the substitute part, which exhibits lower gate charge and faster switching characteristics.

Q: Are there any PCB layout considerations when substituting the TSM085P03CS RLG?

A: No layout modifications are required. Both parts utilize identical 8-SOIC package geometry with 0.154" width and 3.90mm dimensions. Existing footprints and land patterns are directly compatible.

Q: What is the significance of the MSL rating difference between these parts?

A: The TSM4459CS RLG carries MSL 3 (168 Hours), requiring controlled moisture exposure during storage and handling. The TSM085P03CS RLG carries MSL 1 (Unlimited), eliminating moisture sensitivity constraints and simplifying inventory management and procurement logistics.

Q: How do the input capacitance values affect circuit performance?

A: The substitute part exhibits lower input capacitance (3216 pF versus 6205 pF at 15V Vds). This reduction improves switching speed and reduces driver circuit loading, providing performance benefits in high-frequency switching applications.