Persamaan Transistor D998 B778 |top| <100% LATEST>

Transistor 2SD998 (D998) dan 2SB778 (B778) adalah pasangan komplementer transistor daya bipolar (BJT) yang sering digunakan pada tahap output amplifier audio berdaya tinggi. Spesifikasi Utama

3. Electrical Characteristics ((T_c = 25^\circ C))

| Parameter | Condition | 2SD998 (NPN) | 2SB778 (PNP) | Unit | | :--- | :--- | :--- | :--- | :--- | | Collector Cutoff Current | (V_CB=120V, I_E=0) | max 10 | max -10 | µA | | Emitter Cutoff Current | (V_EB=5V, I_C=0) | max 10 | max -10 | µA | | DC Current Gain (hFE) | (V_CE=4V, I_C=1A) | 50 to 160 | 50 to 160 | - | | Collector-Emitter Saturation Voltage | (I_C=7A, I_B=0.35A) | max 1.0 | max -1.0 | V | | Base-Emitter Voltage | (V_CE=4V, I_C=1A) | typ 1.0 | typ -1.0 | V | | Transition Frequency (fT) | (V_CE=10V, I_C=0.5A) | typ 15 | typ 15 | MHz | | Thermal Resistance | Junction to case | 1.56 | 1.56 | °C/W | Persamaan Transistor D998 B778

Technical Write-Up: Equivalent Transistors for 2SD998 and 2SB778

1. Introduction

The 2SD998 (NPN) and 2SB778 (PNP) are a complementary pair of power transistors widely used in audio power amplifiers, particularly in the output stages of high-fidelity (Hi-Fi) stereo systems, home theater receivers, and professional PA amplifiers. Known for their high current handling and wide Safe Operating Area (SOA), this pair has become a standard in many Japanese-brand amplifiers from the 1980s–2000s (e.g., Pioneer, Kenwood, Technics, and Sansui). Transistor 2SD998 (D998) dan 2SB778 (B778) adalah pasangan

Note: Do not confuse with TO-247 or TO-3P. MT-200 has wider body and different pin shape. For Repairs: Check the $h_FE$ (gain) before installing

For Repairs: Check the $h_FE$ (gain) before installing. It is best to use matched pairs (one NPN and one PNP with similar gain values) to ensure balanced sound reproduction.
For Upgrades: Replacing them with TIP41C/TIP42C is possible but generally seen as a downgrade in audio fidelity. Replacing with 2SD1559/2SB1106 is the recommended upgrade path.

Their reputation for robust construction, high safe operating area (SOA), and excellent linearity makes them a favorite among audiophiles and repair technicians.