Persamaan Transistor D998 B778 [2026]
If you are repairing a device and cannot find the original D998 or B778, you can use substitutes. When substituting, you must ensure the pinout matches.
Transistor driver (biasanya ukuran TO-220 seperti D669/B649) harus diganti jika D998/B778 short. Driver yang rusak akan membunuh transistor final baru meskipun sudah menggunakan persamaan yang tepat.
Transistor ini memiliki rating sama atau lebih tinggi, pinout sama, dan karakteristik audio yang serupa. Persamaan Transistor D998 B778
| Persamaan NPN (untuk D998) | Persamaan PNP (untuk B778) | Keunggulan | | :--- | :--- | :--- | | 2SC5200 | 2SA1943 | Paling populer (Toshiba). Suara jernih, mudah dicari, harga terjangkau. | | 2SC5242 | 2SA1962 | Fairchild/ON Semi. Vceo lebih tinggi (230V), lebih tahan overvoltage. | | 2SD1047 | 2SB817 | Sanken. Untuk subwoofer, bass lebih padat. | | 2SC3281 | 2SA1302 | Toshiba lawas (legacy). Kualitas audio high-end. |
Catatan: Kelima pasangan di atas menggunakan kemasan TO-264 atau TO-3P yang sama dengan D998/B778. Anda tidak perlu merubah lubang PCB. If you are repairing a device and cannot
How to test with a multimeter (diode mode):
| Test | Red Probe | Black Probe | Expected Reading | | :--- | :--- | :--- | :--- | | NPN (D998) B-E | Base | Emitter | 0.5–0.7V | | NPN (D998) B-C | Base | Collector | 0.5–0.7V | | PNP (B778) E-B | Emitter | Base | 0.5–0.7V | | PNP (B778) C-B | Collector | Base | 0.5–0.7V | Catatan: Kelima pasangan di atas menggunakan kemasan TO-264
Common failures:
| NPN Equivalent | PNP Equivalent | Notes | | :--- | :--- | :--- | | 2SC5200 | 2SA1943 | Very popular; slightly lower Vceo (140V vs 160V) but acceptable for most amps. Higher ft (30 MHz), 150W, 15A. Toshiba. | | MJL4281A | MJL4302A | Superior performance; 230V, 230W, 15A. Requires checking if original circuit voltage is <160V. Onsemi. | | NJW0281G | NJW0302G | Direct upgrade; 250V, 150W, 15A. Excellent SOA. Onsemi. | | 2SC3858 | 2SA1494 | Japanese standard; 200V, 200W, 17A. Slightly larger but very robust. Sanken. |