SCT812B Equivalent & Substitute Parts

Part Overview

The SCT812B is an 800V, 12A standard recovery thyristor (SCR) in TO-220-3 through-hole packaging manufactured by SMC Diode Solutions. This component is classified as obsolete, making identification of suitable substitute parts essential for ongoing system support and component procurement. The SCT812B serves as a power control and switching element in applications requiring high-voltage thyristor functionality within the specified current and thermal operating ranges.

Substiute Parts

SCT812B

SMC Diode SolutionsIn Stock: 1337SCT812B Datasheet

Current PartRFQ

SCT812C

SMC Diode SolutionsIn Stock: 1072SCT812C Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SCT812B is determined by strict equivalence across the following critical parameters:

• Voltage Rating (Off State): 800V minimum blocking voltage capability
• Current Rating (On State): 12A RMS maximum on-state current
• Gate Trigger Characteristics: Vgt ≤ 1.5V and Igt ≤ 15mA for gate control compatibility
• On-State Voltage Drop: Vtm ≤ 1.55V for thermal and efficiency considerations
• Hold Current: Ih ≤ 50mA for latching behavior
• Surge Current Capability: Itsm = 140A @ 50Hz for transient protection
• Package Configuration: TO-220-3 through-hole mounting for mechanical and thermal interface compatibility
• SCR Type: Standard Recovery classification for switching speed characteristics

Substitute parts must maintain equivalence across all listed parameters to ensure functional and thermal compatibility within the original application circuit.

Parameter Comparison

Engineering Selection Recommendations

The SCT812C is the manufacturer-recommended substitute for the obsolete SCT812B. Both components share identical electrical specifications, functional descriptions, and base product designation (SCT812), confirming direct functional equivalence.

The SCT812C maintains active product status, ensuring ongoing availability and supply chain continuity. Both parts comply with identical export control classifications (ECCN: EAR99) and tariff codes (HTSUS: 8541.30.0080), supporting regulatory and procurement consistency.

The SCT812B is certified ROHS3 compliant. Verification of RoHS compliance status for the SCT812C should be confirmed through the manufacturer's current documentation prior to procurement for applications with RoHS requirements.

Frequently Asked Questions (FAQ)

Q: Can the SCT812C directly replace the SCT812B in existing designs?

A: Yes. The SCT812C is the manufacturer-recommended substitute and maintains identical electrical specifications, gate trigger characteristics, on-state voltage drop, and thermal operating range. No circuit modifications are required for direct substitution.

Q: Are there packaging differences between SCT812B and SCT812C?

A: Both components use TO-220-3 through-hole packaging. The mechanical and thermal interface characteristics are identical, supporting direct board-level replacement without modification to mounting hardware or thermal management provisions.

Q: Why is the SCT812B listed as obsolete?

A: The SCT812B has reached end-of-life status. The SCT812C represents the active continuation of this product line from SMC Diode Solutions, maintaining full electrical and mechanical compatibility while ensuring ongoing supply availability.

Q: What compliance certifications apply to both parts?

A: Both the SCT812B and SCT812C are classified under ECCN: EAR99 for export control purposes and HTSUS: 8541.30.0080 for tariff classification. The SCT812B is confirmed ROHS3 compliant; RoHS status for the SCT812C should be verified with current manufacturer documentation.

Q: Are there any gate trigger or hold current differences that affect circuit design?

A: No. Both components maintain identical gate trigger voltage (Vgt ≤ 1.5V), gate trigger current (Igt ≤ 15mA), and hold current (Ih ≤ 50mA) specifications. Gate drive circuits and control logic require no modification.