onsemi 2SC4429M

Overview

2SC4429M from SANYO is an NPN triple diffused planar silicon transistor designed for high-voltage switching regulator applications, featuring 800 V V_CEO, 8 A I_C, fast switching (t_f = 0.1 µs typ), wide SOA, and TO-3PML micaless package. It serves as a primary power switch in offline SMPS designs operating up to 400 V DC bus.

For engineers reviewing the 2SC4429M datasheet, pinout, applications, or equivalent options, key selection criteria include breakdown voltage margin, safe operating area under pulse conditions, thermal resistance in non-heatsinked mounting, h_FE rank consistency (K/L/M), and gate drive compatibility with standard bipolar drivers in flyback and forward converters.

Technical Context

This device employs SANYO's MBIT process to achieve high ruggedness and stable gain across temperature. Its 800 V V_CEO rating supports 400 V DC link operation with ≥2× safety margin, while the 0.1 µs typical fall time enables efficient operation at 50–100 kHz switching frequencies.

The TO-3PML package provides low thermal resistance (R_th(j-c) = 0.5°C/W) and eliminates mica insulation-reducing mounting complexity and thermal interface resistance. Electrical characteristics are specified at T_c = 25°C with pulsed conditions (PW ≤ 300 µs, duty ≤ 10%) to reflect real-world switching use.

Key Specifications

Pinout & Package

Package: TO-3PML (SANYO designation), micaless metal package with isolated collector tab, optimized for direct heatsink mounting without insulating washers.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 2SC4429M, the 2SC4759 offers greater voltage safety margin at the cost of switching speed, while the BU508A trades speed and compactness for extreme ruggedness-making 2SC4429M optimal for modern 50–100 kHz SMPS where balance of voltage, speed, and thermal performance is critical.

Availability

2SC4429M is available at Aetrix Electronics and suitable for AC-DC power adapters, industrial switching supplies, and LED driver power stages requiring stable component supply, long-term BOM continuity, and traceable sourcing.

Supply support for 2SC4429M 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 known for high-reliability power devices and analog ICs before its acquisition by Panasonic in 2012; its power transistor legacy remains widely deployed in industrial power systems.

The 2SC4429M belongs to SANYO's high-voltage bipolar transistor family engineered specifically for offline switching regulators, emphasizing ruggedness, SOA integrity, and thermal efficiency in compact TO-3PML packaging.

FAQ

What is the maximum continuous collector current rating for the 2SC4429M?

The 2SC4429M is rated for 8 A continuous collector current (I_C) at T_c = 25°C. Derating is required above this case temperature-e.g., ~5.5 A at T_c = 80°C per the PC–T_a curve. This rating assumes proper heatsinking and pulsed-base drive per the datasheet test conditions.

Does the 2SC4429M have a built-in base-emitter resistor or protection diode?

No, the 2SC4429M is a discrete NPN bipolar transistor without integrated base resistors or protection diodes. External base drive circuitry-including current-limiting resistors and clamping diodes-is required to ensure safe turn-on/turn-off and prevent second breakdown during switching transitions.

What does the "M" suffix in 2SC4429M indicate?

The "M" suffix in 2SC4429M denotes a specific h_FE rank group-typically corresponding to h_FE = 200–400 at I_C = 0.6 A, V_CE = 5 V. SANYO classified 2SC4429 into K (100–200), L (150–300), and M (200–400) bins; the M grade ensures tighter gain consistency for predictable base drive design.

Can the 2SC4429M be used in avalanche mode?

No, the 2SC4429M is not rated or characterized for controlled avalanche operation. Its Absolute Maximum Ratings specify V_CEO = 800 V as a non-repetitive limit, and the datasheet provides no SOA data beyond forward-bias pulse conditions. Avalanche use risks parametric shift or catastrophic failure.

Is the collector terminal of the 2SC4429M electrically isolated from the metal package tab?

No-the collector (Pin 2) is directly connected to the metal tab in the TO-3PML package. When mounting to a heatsink, electrical isolation is required unless the heatsink is held at collector potential. The "micaless" designation means no insulating washer is needed *if* isolation is handled elsewhere in the mechanical design.