Specs side by side
2 parts compared · 14 differing specs across 14 total parameters.
| Parameter | ||
|---|---|---|
| Supply voltage | - | Same 40V class across the trio. |
| Memory & Peripherals | - | The PNP complement follows the same generation rule: the 2N4403 pairs with the 2N4401 exactly as the 2N3906 pairs with the 2N3904. |
| Case | TO-92 / SOT-23 | TO-92 |
| Compatibility Level | - | 100% Drop-in (Zero Code Change) |
| Component Category | Small-Signal Transistors | - |
| Core & Architecture | - | The in-between option of the US lineup: 40V, 600mA, E-B-C order, fT 250MHz - closer to the 2N3904 noise behavior than the 2N2222A, at higher current than the 2N3904. |
| Firmware Notes | - | Where a circuit oscillates on 2N2222A gain bandwidth or lacks margin on 2N3904 current, this is the middle rung - same pins, same family culture, the small-signal engineering compromise. |
| Hardware Notes | - | TO-92, E-B-C, matching the 2N3904 socket directly. |
| Lead Time Advantage | - | Shenzhen Spot Stock (24-48h Dispatch) |
| Market Reality | The 2N3904 NPN and its 2N3906 PNP complement are the American small-signal standard: 40V, 200mA, 625mW, TO-92 with E-B-C lead order, gain optimized around 10mA, and SOT-23 twins (MMBT3904 / MMBT3906) in more new designs than the through-hole originals. The repair trap has two layers: the European counterpart BC547 is C-B-E in the same TO-92 body - a straight insertion swaps emitter and collector into reverse-active operation - and the SOT-23 twins number their pins 1 = Base, 2 = Emitter, 3 = Collector, which follows neither lead order. Every substitution in this family answers the pinout question before the electrical one. | - |
| Reference Part | - | 2N3904 / 2N3906 |
| Role In Circuit | Original Reference Part | - |
| Sourcing Advantage | - | Stocked; the professional middle option the module trade forgets exists. |
| Sourcing Status | Active Shenzhen Spot Sourcing (24–48h) | - |
Parts
- 2N3904 / 2N3906 · onsemi
- 2N4401 / 2N4403 · onsemi