component
S8550D331
Public Made by Adomby adom
ALJ Bipolar (BJT), TO-92. Pinout cross-checked by two models against the datasheet, KiCad symbol/footprint/3D.
3D Model
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Symbol & Footprint
Schematic Symbol
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PCB Footprint
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Datasheet
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README
markdownS8550D331
ALJ · Bipolar (BJT) · TO-92
S8550D331 from ALJ, in a TO-92. Pinout and pin descriptions extracted from the manufacturer datasheet (extract_pins, cross-checked by a second model); symbol, footprint, and 3D from KiCad-official CAD.
Pinout
| Pin | Name | Type | Function |
|---|---|---|---|
| 1 | Emitter | passive | Emitter terminal of the PNP transistor; the datasheet's absolute maximum emitter-base voltage VEBO is -5 V and emitter-base breakdown V(BR)EBO is -5 V at IE=-100µA. |
| 2 | Base | passive | Base terminal; the datasheet's saturation test uses IB=-50mA with IC=-500mA, giving VBE(sat) of -1.2 V max, and emitter-base cut-off current IEBO is -100 nA max at VEB=-3V. |
| 3 | Collector | passive | Collector terminal; the datasheet limits are VCBO -40 V, VCEO -25 V, IC -800 mA and PC 625 mW. |
Key specifications
| Parameter | Value |
|---|---|
| Manufacturer | ALJ |
| Package | TO-92 |
| Category | Transistors/Thyristors |
| Pins | 3 |
Electrical characteristics
Limits as printed in the datasheet (page.json metadata.characteristics carries them as data).
| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| Collector-base voltage | VCBO | -40 | V | Ta=25°C unless otherwise noted | 1 | ||
| Collector-emitter voltage | VCEO | -25 | V | Ta=25°C unless otherwise noted | 1 | ||
| Emitter-base voltage | VEBO | -5 | V | Ta=25°C unless otherwise noted | 1 | ||
| Collector current | IC | -800 | mA | Ta=25°C unless otherwise noted | 1 | ||
| Collector power dissipation | PC | 625 | mW | Ta=25°C unless otherwise noted | 1 | ||
| Junction temperature | Tj | 150 | °C | 1 | |||
| Storage temperature | Tstg | -55 | 150 | °C | 1 | ||
| DC current gain (hFE(1)) | hFE(1) | 100 | 200 | VCE=-1V, IC=-50mA | 1 | ||
| DC current gain (hFE(2)) | hFE(2) | 50 | VCE=-1V, IC=-500mA | 1 | |||
| Collector-base breakdown voltage | V(BR)CBO | -40 | V | IC=-100µA,IE=0 | 1 | ||
| Collector-emitter breakdown voltage | V(BR)CEO | -25 | V | IC=-1mA,IB=0 | 1 | ||
| Emitter-base breakdown voltage | V(BR)EBO | -5 | V | IE=-100µA,IC=0 | 1 | ||
| Collector cut-off current | ICBO | -100 | nA | VCB=-40V,IE=0 | 1 | ||
| Emitter cut-off current | IEBO | -100 | nA | VEB=-3V,IC=0 | 1 | ||
| Collector-emitter saturation voltage | VCE(sat) | -0.6 | V | IC=-500mA,IB=-50mA | 1 | ||
| Base-emitter saturation voltage | VBE(sat) | -1.2 | V | IC=-500mA,IB=-50mA | 1 | ||
| Transition frequency | fT | 150 | MHz | VCE=-6V,IC=-20mA,f=30MHz | 1 |
CAD (KiCad official)
- Symbol:
S8550D331 - Footprint:
Package_TO_SOT_THT:TO-92_Inline - 3D model: TO-92 (KiCad packages3D, STEP)
- 3D model files:
s8550d331-etched.step/s8550d331-etched.glbcarry the MPN laser-etched on the die in a toggleableAdom.LaserEtchgroup (Fusion-ready);s8550d331.step/s8550d331.glbare the bare package body.
Provenance
Data extracted from the manufacturer datasheet, not a distributor listing:
- Datasheet: ALJ datasheet (2 pp, sha256
81c15b1760cef7cf, retrieved 2026-10-18, tier: lcsc) - Extractor: parts-factory
2.0.0/extract_pins 0.3, primaryclaude-haiku-5-5(text), consensusclaude-sonnet-5-5(agreed), guards: pin_guards 0.1: passed. Pins are checked against the footprint pad set and their cited datasheet pages before publish. - CAD: KiCad official libraries (CC-BY-SA 4.0).