S4025NTP Equivalent & Substitute Parts

Part Overview

The S4025NTP is a Silicon Controlled Rectifier (SCR) manufactured by Littelfuse Inc., rated for 400V off-state voltage with 25A RMS on-state current capability. This thyristor is designed for surface mount applications in the TO-263 (D2PAK) package format. The component is currently in active production status with 2321 units available in inventory. Alternative part selection becomes necessary when supply constraints occur, when higher voltage ratings are required for system redesign, or when alternative packaging formats from qualified suppliers are preferred while maintaining functional compatibility.

Substiute Parts

S4025NTP

Littelfuse Inc.In Stock: 2365S4025NTP Datasheet

Current PartRFQ

TN2540-600G-TR

STMicroelectronicsIn Stock: 1145TN2540-600G-TR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

The TN2540-600G-TR from STMicroelectronics qualifies as a manufacturer-recommended substitute for the S4025NTP based on the following substitution criteria:

Matching Parameters:

• On-state current rating: 25A RMS (identical)
• On-state voltage drop (Vtm): 1.6V maximum (identical)
• Hold current (Ih): 50mA maximum (identical)
• Package format: D2PAK surface mount (identical mechanical compatibility)
• Operating temperature range: -40°C to 125°C (identical)
• SCR type: Standard Recovery (identical)
• RoHS3 compliance (identical regulatory status)

Allowable Variation:

• Off-state voltage: 600V (higher than 400V requirement) — acceptable for applications where the main part's 400V rating is sufficient, as the substitute provides additional voltage margin
• Gate trigger voltage (Vgt): 1.3V maximum (lower than 1.5V) — acceptable as lower trigger voltage maintains or improves gate sensitivity
• Gate trigger current (Igt): 40mA maximum (higher than 35mA) — acceptable as gate drive circuits typically accommodate this range
• Off-state leakage current: 5µA (lower than 10µA) — acceptable as reduced leakage improves performance

The substitute maintains functional equivalence through identical current handling, thermal characteristics, and package compatibility while providing enhanced voltage margin and reduced leakage characteristics.

Parameter Comparison

Engineering Selection Recommendations

The TN2540-600G-TR is suitable as a direct substitute for the S4025NTP in applications where the following conditions are met:

• Circuit design accommodates the 600V off-state voltage rating without adverse effects
• Gate drive circuitry is compatible with the 1.3V trigger voltage and 40mA trigger current specifications
• Both components maintain ROHS3 compliance and REACH unaffected status, ensuring regulatory equivalence
• Both components are classified as active products with established supply chains
• Thermal management and PCB layout remain unchanged due to identical package format and operating temperature range

The substitute provides enhanced performance characteristics through higher voltage margin and reduced off-state leakage current, making it suitable for applications requiring improved reliability margins.

Frequently Asked Questions (FAQ)

Q: Can the TN2540-600G-TR replace the S4025NTP in a 400V circuit?

A: Yes. The TN2540-600G-TR is rated for 600V off-state voltage, which exceeds the 400V requirement of the original circuit. The substitute will function correctly in applications designed for the S4025NTP's 400V rating.

Q: Are there differences in gate drive requirements between these parts?

A: The TN2540-600G-TR has a lower gate trigger voltage (1.3V vs. 1.5V) and slightly higher gate trigger current (40mA vs. 35mA). Existing gate drive circuits designed for the S4025NTP will operate the substitute within specification.

Q: Do both parts use the same package?

A: Yes. Both the S4025NTP and TN2540-600G-TR use the TO-263-3 D2PAK surface mount package with identical pinout and mechanical dimensions. No PCB layout modifications are required.

Q: What is the difference in leakage current between these parts?

A: The TN2540-600G-TR has a maximum off-state leakage current of 5µA compared to the S4025NTP's 10µA. Lower leakage current improves efficiency in applications sensitive to standby power consumption.

Q: Are both parts RoHS compliant?

A: Yes. Both the S4025NTP and TN2540-600G-TR are ROHS3 compliant and REACH unaffected, meeting current environmental and regulatory requirements.

Q: What is the on-state current rating for both parts?

A: Both parts are rated for 25A RMS on-state current with identical 1.6V maximum on-state voltage drop, ensuring equivalent thermal and electrical performance in conducting mode.