onsemi 2SB1223

Overview

2SB1223 from SANYO is a PNP epitaxial planar silicon Darlington transistor in TO-220ML package, rated for −70 V V_CEO, −4 A I_C, 20 W P_C (T_C=25°C), with h_FE ≥ 2000 at I_C = −2 A, and optimized for motor driver and constant-voltage regulator control circuits.

For engineers reviewing the 2SB1223 datasheet, pinout, applications, or equivalent options, key selection criteria include guaranteed DC current gain at high collector current, wide safe operating area (SOA) under pulsed conditions, low V_CE(sat) ≤ −1.0 V at I_C/I_B = 500, and micaless TO-220ML mounting compatibility.

Technical Context

This Darlington pair integrates two PNP transistors in cascade to achieve high current gain and robust switching performance. It operates with base-emitter saturation voltage V_BE(sat) ≤ −1.0 V and collector-emitter saturation voltage V_CE(sat) ≤ −1.0 V at I_C = −2 A and I_C/I_B = 500, enabling efficient drive of inductive loads without external base resistors in many configurations.

The device features a wide SOA up to −6 A peak current and −70 V, validated for 1 ms to 100 ms single-pulse operation. Its thermal design supports direct mounting on heatsinks via the insulated tab, eliminating mica insulation requirements while maintaining electrical isolation between collector and heatsink.

Key Specifications

Pinout & Package

SANYO TO-220ML package: insulated metal tab (collector-connected), no mica required, vertical mounting orientation, 3-pin through-hole configuration.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar PNP Darlington transistor applications.

Compared with 2SB1223, 2SB1182 offers reduced voltage margin and gain headroom, while MJD2955 trades gain and thermal mounting simplicity for raw current capacity-neither provides identical combination of high h_FE, insulated TO-220ML, and −70 V/−4 A rating.

Availability

2SB1223 is available at Aetrix Electronics and suitable for motor drivers, printer hammer drivers, and constant-voltage regulators requiring stable component supply across industrial equipment lifecycles.

Supply support for 2SB1223 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 discrete devices, analog ICs, and optoelectronics before its acquisition by ON Semiconductor in 2011.

The 2SB1223 belongs to SANYO's high-reliability PNP Darlington transistor family designed specifically for industrial actuator control, where high current gain and robust SOA are essential for driving inductive loads without secondary protection.

FAQ

What is the maximum junction temperature rating for the 2SB1223?

The 2SB1223 has a maximum junction temperature (T_j) rating of +150°C, as specified in its Absolute Maximum Ratings table. This limit applies under all operating conditions, including pulsed and DC modes. Exceeding this temperature risks permanent parametric shift or catastrophic failure. Thermal design must ensure T_j remains below +150°C using appropriate heatsinking and ambient derating per the PC–T_C curve in the datasheet.

Is the 2SB1223 pin-compatible with the 2SD1825 listed in the same ordering number?

No, the 2SB1223 and 2SD1825 are complementary devices-not pin-compatible. The 2SB1223 is a PNP Darlington transistor with pinout Base–Collector–Emitter (1–2–3), while the 2SD1825 is an NPN Darlington with identical physical package but reversed polarity and different electrical characteristics. Their shared ordering number reflects co-packaging for driver pairs, not interchangeability.

Does the 2SB1223 require a base resistor in typical switching applications?

Yes, the 2SB1223 requires an external base resistor to limit base current and ensure proper saturation. With h_FE ≥ 2000, a typical design uses I_B ≈ I_C/500 to achieve V_CE(sat) ≤ −1.0 V. For example, at I_C = −2 A, I_B should be ≈ −4 mA, requiring a base resistor calculated from available drive voltage and V_BE(sat) ≈ −1.0 V.

Can the 2SB1223 be used in linear regulator applications?

Yes, the 2SB1223 is explicitly rated for linear regulator use, with 20 W collector dissipation at T_C = 25°C and SOA validated for DC operation. Its low V_CE(sat) and high h_FE reduce base drive complexity and improve thermal efficiency compared to standard transistors. However, thermal management must account for worst-case power dissipation (V_IN − V_OUT) × I_LOAD.

What does "micaless package" mean for the 2SB1223?

The "micaless" designation means the 2SB1223's TO-220ML package incorporates built-in electrical insulation between the collector-connected metal tab and the mounting surface. Unlike standard TO-220 devices requiring external mica washers and silicone grease, the 2SB1223 can be mounted directly to a heatsink with thermal paste only-eliminating insulator aging, arcing risk, and assembly steps while maintaining creepage/clearance compliance.