BT149G,412 Equivalent & Substitute Parts

Part Overview

The BT149G,412 is a sensitive gate silicon-controlled rectifier (SCR) rated for 600 V off-state voltage and 800 mA RMS on-state current in a TO-92-3 through-hole package. Manufactured by WeEn Semiconductors, this component is classified as Active product status and is RoHS Compliant. Equivalent and substitute parts are identified based on matching electrical ratings, gate sensitivity characteristics, and package compatibility to support circuit design flexibility and supply chain continuity.

Substiute Parts

BT149G,412

WeEn SemiconductorsIn Stock: 1166BT149G,412 Datasheet

Current PartRFQ

S6X8ESRP

Littelfuse Inc.In Stock: 2494S6X8ESRP Datasheet

DirectRFQ

S4X8ES

Littelfuse Inc.In Stock: 80493S4X8ES Datasheet

SimilarRFQ

S6X8ES

Littelfuse Inc.In Stock: 5201S6X8ES Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the BT149G,412 are classified into two categories based on electrical parameter alignment:

Direct Equivalent (S6X8ESRP): Matches all critical electrical parameters including 600 V off-state voltage, 800 mV gate trigger voltage, 200 µA gate trigger current, and 800 mA RMS on-state current. Packaging is TO-92-3 with formed leads. This part is suitable for direct replacement in applications requiring identical electrical performance.

Similar Voltage Rating (S6X8ES): Matches the 600 V off-state voltage, gate sensitivity parameters, and on-state current ratings. Packaging is TO-92-3 in bulk form. This part provides equivalent electrical functionality with identical voltage and current specifications.

Lower Voltage Alternative (S4X8ES): Rated for 400 V off-state voltage with matching gate sensitivity (800 mV, 200 µA) and on-state current (800 mA RMS). Packaging is TO-92-3 in bulk form. This part is suitable only for applications where the circuit operates at or below 400 V.

Parameter Comparison

Engineering Selection Recommendations

For 600 V Applications: S6X8ESRP and S6X8ES are direct electrical equivalents to the BT149G,412. Both maintain identical off-state voltage, gate trigger specifications, and on-state current ratings. S6X8ESRP is supplied in cut tape packaging with formed leads, while S6X8ES is supplied in bulk packaging. Both are ROHS3 Compliant and Active product status.

For 400 V Applications: S4X8ES provides equivalent gate sensitivity and on-state current performance at a reduced voltage rating. This part is suitable only when circuit design operates at or below 400 V off-state voltage. S4X8ES is ROHS3 Compliant and Active product status.

Compliance Considerations: All substitute parts maintain RoHS compliance (ROHS3 standard for Littelfuse parts versus RoHS Compliant for the main part). All parts are classified as Active product status, ensuring continued availability and support.

Frequently Asked Questions (FAQ)

Q: Can S6X8ESRP replace BT149G,412 in all applications? A: S6X8ESRP matches all critical electrical parameters (600 V, 800 mV gate trigger, 200 µA gate trigger current, 800 mA RMS on-state current) and package type (TO-92-3). It is a direct electrical equivalent suitable for replacement in circuits designed for the BT149G,412.

Q: What is the difference between S6X8ESRP and S6X8ES? A: Both parts have identical electrical ratings and package type (TO-92-3). The primary difference is packaging format: S6X8ESRP is supplied in cut tape with formed leads, while S6X8ES is supplied in bulk. Electrical performance is equivalent.

Q: When should S4X8ES be used instead of S6X8ES? A: S4X8ES is rated for 400 V off-state voltage, compared to 600 V for S6X8ES. Use S4X8ES only in applications where the circuit operates at or below 400 V. For circuits requiring 600 V rating, use S6X8ES or S6X8ESRP.

Q: Are all substitute parts compatible with the TO-92-3 package footprint? A: Yes. All substitute parts (S6X8ESRP, S6X8ES, S4X8ES) use the TO-92-3 (TO-226AA) through-hole package, ensuring mechanical and electrical compatibility with existing PCB designs.

Q: Do the substitute parts meet the same RoHS requirements? A: Yes. All substitute parts are ROHS3 Compliant. The main part BT149G,412 is RoHS Compliant. Both standards meet environmental and hazardous substance restrictions for electronic components.