Toshiba Semiconductor and Storage 2SA1943N(S1,E,S)

2SA1943N(S1,E,S) from Toshiba is a silicon PNP bipolar power transistor designed for high-voltage, high-current audio amplifier output stages. It delivers V_CEO = −230 V (min), I_C = −15 A (DC), and P_C = 150 W at T_c = 25 °C, housed in a TO-3P(N) metal package with heatsink-connected collector. It is specifically recommended for 100-W high-fidelity audio amplifiers.

For engineers reviewing the 2SA1943N(S1,E,S) datasheet, 2SA1943N(S1,E,S) pinout, 2SA1943N(S1,E,S) application, or 2SA1943N(S1,E,S) equivalent, key selection criteria include guaranteed V_CEO rating, complementary pairing with 2SC5200N, thermal resistance R_th(j–c) ≤ 0.83 °C/W, safe operating area (SOA) compliance, and RoHS-compliant marking per Rev. 2.0 (2015).

Technical Context

This PNP transistor uses triple-diffused silicon construction to achieve high breakdown voltage and stable DC current gain (h_FE = 80–160 at I_C = −1 A). Its internal structure places the collector on the metal tab for direct heatsinking, enabling high-power dissipation without external thermal interface degradation.

It operates as a linear switching or Class AB output device with V_CE(sat) ≤ −3.0 V at I_C = −8 A / I_B = −0.8 A and f_T = 30 MHz (typ.), supporting wideband audio frequency response up to 20 kHz with low distortion in push-pull configurations.

Key Specifications

Pinout & Package

Package: TO-3P(N), also designated 2-16C1S by Toshiba; metal case with insulated mounting hole; weight 4.6 g (typ.); collector electrically connected to heatsink tab.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MJE15034 and BDW84C, the 2SA1943N(S1,E,S) offers superior voltage rating, lower thermal resistance, and integrated heatsink connectivity-making it uniquely suited for high-fidelity 100-W amplifier output stages requiring reliability and symmetry with 2SC5200N.

Availability

2SA1943N(S1,E,S) is available at Aetrix Electronics and suitable for high-fidelity audio amplifiers, professional PA systems, and industrial linear power regulators requiring stable component supply and long-term manufacturability.

Supply support for 2SA1943N(S1,E,S) 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

Toshiba Electronic Devices & Storage Corporation designs and manufactures discrete semiconductors, power devices, and logic ICs with emphasis on reliability, thermal performance, and industrial-grade specifications.

The 2SA1943N(S1,E,S) belongs to Toshiba's legacy high-power audio transistor family, engineered specifically for symmetrical, high-voltage, high-fidelity linear amplifier output stages requiring matched PNP/NPN pairs.

FAQ

What is the maximum continuous collector current rating for the 2SA1943N(S1,E,S)?

The 2SA1943N(S1,E,S) has a maximum DC collector current rating of −15 A at T_c = 25 °C. Derating is required above this case temperature per the absolute maximum ratings table; at T_c = 100 °C, the usable I_C drops to approximately −7.5 A to maintain junction temperature ≤150 °C. This rating assumes proper heatsinking per the specified R_th(j–c) ≤ 0.83 °C/W.

Is the 2SA1943N(S1,E,S) pin-compatible with the 2SC5200N?

No-the 2SA1943N(S1,E,S) and 2SC5200N are complementary PNP/NPN devices but have identical TO-3P(N) mechanical packaging and matching pinout (Base–Collector–Emitter), enabling direct physical pairing in push-pull circuits. However, they are not functionally interchangeable; each must be placed in its correct polarity position within the circuit. The 2SA1943N(S1,E,S) serves as the PNP half of the pair.

What does the marking "(S1,E,S)" indicate on the 2SA1943N(S1,E,S) part number?

The suffix "(S1,E,S)" denotes Toshiba's internal package variant and marking code: "S1" indicates the TO-3P(N) package with specific lead frame and mold compound; "E" signifies RoHS-compliant lead-free plating; "S" identifies the revision level and production lot traceability format. This full designation appears on the device body and ensures alignment with Rev. 2.0 (2015) datasheet specifications.

Can the 2SA1943N(S1,E,S) be used in switching power supplies?

The 2SA1943N(S1,E,S) is optimized for linear operation-not switching. Its relatively slow turn-off characteristics (no specified t_f or t_on in the datasheet), high stored charge, and lack of avalanche rating make it unsuitable for hard-switching SMPS applications. It is validated for Class AB audio amplifiers and linear regulators where SOA, thermal stability, and analog linearity are prioritized over switching speed.

Does the 2SA1943N(S1,E,S) require derating for operation above 25 °C case temperature?

Yes-derating is mandatory. The 2SA1943N(S1,E,S)'s absolute maximum collector power dissipation decreases linearly above T_c = 25 °C, with full derating to zero at T_c = 150 °C. Per the datasheet, the derating factor is 1.2 W/°C above 25 °C. For example, at T_c = 85 °C, maximum allowable P_C = 150 W − (85 − 25) × 1.2 = 78 W. This ensures junction temperature remains within the 150 °C limit.