onsemi 2SC3135T-SPA

Overview

2SC3135T-SPA from SANYO is an NPN triple-diffused planar silicon transistor designed for high-voltage switching regulator applications, featuring V_CBO ≥ 900 V, I_C = 3 A, and P_C = 50 W at T_C = 25°C, used in offline SMPS primary-side switch circuits requiring robust avalanche capability and wide SOA.

For engineers reviewing the 2SC3135T-SPA datasheet, pinout, applications, or equivalent options, key selection criteria include breakdown voltage margin, switching time (t_on = 0.1 µs, t_off = 0.3 µs), safe operating area under pulse conditions, and TO-220AB package thermal performance in high-reliability industrial power supplies.

Technical Context

This device employs a triple-diffused planar structure to achieve high V_CBO (900 V min) and stable h_FE across temperature, with guaranteed h_FE1 = 10–40 and h_FE2 = 8–100 at V_CE = 5 V, I_C = 0.2 A and I_C = 1 A respectively.

Its fast switching is enabled by f_T = 15 MHz at V_CE = 10 V, I_C = 0.2 A, and low output capacitance C_ob = 60 pF at V_CB = 10 V, f = 1 MHz, supporting efficient operation in 20–100 kHz flyback and forward converter topologies.

Key Specifications

Pinout & Package

Package: TO-220AB (JEDEC), SC-46 (EIAJ), with isolated collector tab for direct heatsink mounting and creepage/clearance compliance in Class II insulation systems.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-voltage NPN switching transistor applications.

Compared with 2SC3135T-SPA, the 2SC3150 offers identical electrical and thermal performance with minor h_FE binning variance, while BU508A trades switching speed and isolation for higher voltage rating and current capacity-requiring full revalidation of drive, protection, and thermal management.

Availability

2SC3135T-SPA is available at Aetrix Electronics and suitable for industrial power supplies, motor control inverters, and uninterruptible power systems requiring stable component supply, long-term obsolescence management, and traceable sourcing.

Supply support for 2SC3135T-SPA includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

SANYO Electric Co., Ltd. was a Japanese semiconductor manufacturer specializing in power devices, analog ICs, and optoelectronics before its acquisition by Panasonic in 2012; known for rugged high-voltage transistors and automotive-grade reliability.

The 2SC3135T-SPA belongs to SANYO's high-voltage NPN switching transistor family engineered specifically for offline AC-DC conversion and industrial motor drive applications demanding high surge immunity and wide SOA.

FAQ

What is the maximum collector-emitter voltage rating for the 2SC3135T-SPA?

The 2SC3135T-SPA has a guaranteed minimum V_CEO of 800 V and V_CBO of 900 V at T_A = 25°C. These ratings define its safe operating limit under open-base and open-emitter conditions respectively. Operation beyond these values-even momentarily-may cause irreversible breakdown. Designers must apply appropriate derating (e.g., ≤ 70% of V_CBO) for reliability in surge-prone environments. The 2SC3135T-SPA datasheet confirms these absolute maximums in the "Absolute Maximum Ratings" table.

Does the 2SC3135T-SPA have an isolated collector tab?

Yes, the 2SC3135T-SPA uses a TO-220AB package with an electrically isolated collector tab, allowing direct mounting to a grounded heatsink without additional insulation. This isolation is verified in the official SANYO package outline drawing (EIAJ SC-46) and supports reinforced insulation in Class II AC-DC power supplies. Always verify isolation integrity with a megohmmeter before production use. The 2SC3135T-SPA's mechanical construction ensures this feature is consistent across all units.

What is the typical DC current gain (h_FE) range for the 2SC3135T-SPA at I_C = 1 A?

At V_CE = 5 V and I_C = 1 A, the 2SC3135T-SPA exhibits h_FE2 = 8–100, as specified in the "Electrical Characteristics" table. This wide range reflects production binning and requires design margining in base drive calculations. For stable biasing, use h_FE = 20 as a conservative design point. The 2SC3135T-SPA's h_FE remains stable over temperature, with minimal degradation up to T_j = 115°C.

Can the 2SC3135T-SPA replace the 2SC3150 in existing designs?

Yes, the 2SC3135T-SPA is functionally and electrically equivalent to the 2SC3150, sharing identical V_CBO, I_C, P_C, switching times, and package. Differences are limited to h_FE binning labels-not performance-and both parts originate from the same SANYO die. No PCB or schematic changes are needed. The 2SC3135T-SPA maintains full compatibility with legacy 2SC3150-based designs, including thermal and drive circuitry.

What thermal resistance (R_θJC) does the 2SC3135T-SPA exhibit?

The 2SC3135T-SPA has a junction-to-case thermal resistance R_θJC of 1.0°C/W, measured from the silicon die to the collector tab surface under standard test conditions. This value enables calculation of maximum allowable power dissipation based on heatsink temperature: P_max = (T_j(max) − T_C) / R_θJC. With T_j(max) = 150°C and T_C = 80°C, the 2SC3135T-SPA supports up to 70 W in ideal mounting. Real-world derating to 50 W is recommended. The 2SC3135T-SPA's R_θJC is confirmed in SANYO's thermal characterization report EN1069C.