T107B1 SCR Thyristor Equivalent & Substitute Parts

Part Overview

The T107B1 is a 200V, 4A sensitive gate SCR (Silicon Controlled Rectifier) manufactured by Littelfuse in a TO-202 through-hole package. This component is classified as obsolete, making identification of functionally equivalent alternatives essential for ongoing system maintenance and new design implementations. The sensitive gate characteristic enables reliable triggering at low gate current levels, making it suitable for applications requiring minimal gate drive circuitry.

Substiute Parts

T107B1

LittelfuseIn Stock: 741T107B1 Datasheet

Current PartRFQ

S4004VS2TP

Littelfuse Inc.In Stock: 2208S4004VS2TP Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the T107B1 is determined by the following critical parameters:

• SCR Type: Must be Sensitive Gate to maintain low gate trigger current requirements (Igt ≤ 500 µA)
• Gate Trigger Voltage (Vgt): Maximum 800 mV ensures compatibility with existing gate drive circuits
• On-State Current Rating (It RMS): Minimum 4A to handle the same load current
• Operating Temperature Range: Must encompass -40°C to 110°C for thermal compatibility
• RoHS Compliance: ROHS3 Compliant status required for regulatory alignment

The S4004VS2TP qualifies as a substitute based on these criteria. While it features a higher off-state voltage rating (400V vs. 200V), this represents an uprating that does not compromise circuit functionality. The sensitive gate characteristic, gate trigger parameters, on-state current rating, and temperature range remain compatible with the original T107B1 application requirements.

Parameter Comparison

Engineering Selection Recommendations

The S4004VS2TP is the designated manufacturer-recommended substitute for the obsolete T107B1. Selection of this alternative is supported by:

• Product Status: S4004VS2TP maintains Active status, ensuring continued availability and supply chain stability
• Regulatory Compliance: Both components are ROHS3 Compliant, maintaining environmental and regulatory alignment
• Electrical Compatibility: Gate trigger parameters and on-state current ratings are directly compatible with T107B1 circuit designs
• Performance Enhancement: The S4004VS2TP provides improved on-state voltage characteristics (1.6V vs. 2.5V maximum) and lower gate trigger current (200 µA vs. 500 µA maximum), resulting in reduced power dissipation and simplified gate drive requirements
• Inventory Availability: S4004VS2TP stock levels (2112 pcs) support immediate procurement for replacement and new production

Frequently Asked Questions (FAQ)

Q: Can the S4004VS2TP directly replace the T107B1 in existing circuits?

A: Yes. Both components share identical gate trigger voltage, on-state current rating, hold current, and operating temperature range. The S4004VS2TP's higher voltage rating (400V vs. 200V) does not create compatibility issues in applications designed for 200V operation.

Q: What is the primary difference between these two SCRs?

A: The S4004VS2TP features a higher off-state voltage rating (400V) and improved electrical characteristics including lower on-state voltage drop and reduced gate trigger current. These represent performance enhancements rather than functional changes.

Q: Are there package considerations when substituting?

A: Yes. The T107B1 uses TO-202 Long Tab through-hole packaging, while the S4004VS2TP uses TO-251AA (IPak) through-hole packaging. PCB layout modifications may be required to accommodate the different lead configuration and spacing.

Q: Does the lower gate trigger current of the S4004VS2TP affect circuit operation?

A: No. Lower gate trigger current (200 µA vs. 500 µA maximum) simplifies gate drive circuit design and reduces power consumption. Existing gate drive circuits designed for the T107B1 will operate reliably with the S4004VS2TP.

Q: Are both components RoHS compliant?

A: Yes. Both the T107B1 and S4004VS2TP are ROHS3 Compliant, maintaining regulatory compliance for applications subject to RoHS requirements.