component
BD138
Public Made by Adomby adom
Changjing Bipolar Transistors - BJT, TO-126. 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
markdownBD138
Changjing · Bipolar Transistors - BJT · TO-126
BD138 from Changjing, in a TO-126. 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 emitter-base breakdown voltage V(BR)EBO is -5 V at IE=-0.1mA. |
| 2 | COLLECTOR | passive | Collector terminal of the PNP transistor; the maximum collector current IC is -1.5 A with a collector power dissipation PC of 1.25 W. |
| 3 | BASE | input | Base terminal of the PNP transistor; the base-emitter voltage VBE is -1 V maximum at VCE=-2V, IC=-500mA. |
Key specifications
| Parameter | Value |
|---|---|
| Manufacturer | Changjing |
| Package | TO-126 |
| Category | Triode/MOS Tube/Transistor |
| 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 breakdown voltage | V(BR)CBO | -60 | V | IC= -0.1mA,IE=0 | 2 | ||
| Collector-emitter sustaining voltage | VCEO(SUS) | -60 | V | IC=-0.03A,IB=0 | 2 | ||
| Emitter-base breakdown voltage | V(BR)EBO | -5 | V | IE=-0.1mA,IC=0 | 2 | ||
| Collector cut-off current | ICBO | -0.1 | μA | VCB=-30V,IE=0 | 2 | ||
| Emitter cut-off current | IEBO | -10 | μA | VEB=-5V,IC=0 | 2 | ||
| DC current gain | hFE(1) | 40 | 250 | VCE=-2V, IC=-150mA | 2 | ||
| DC current gain | hFE(2) | 25 | VCE=-2V, IC=-5mA | 2 | |||
| Collector-emitter saturation voltage | VCE(sat) | -0.5 | V | IC=-500mA,IB=-50mA | 2 | ||
| Base-emitter voltage | VBE | -1 | V | VCE=-2V, IC=-500mA | 2 | ||
| Collector-base voltage | VCBO | -60 | V | 1 | |||
| Collector-emitter voltage | VCEO | -60 | V | 1 | |||
| Emitter-base voltage | VEBO | -5 | V | 1 | |||
| Collector current | IC | -1.5 | A | 1 | |||
| Collector power dissipation | PC | 1.25 | W | 1 | |||
| Thermal resistance from junction to ambient | RθJA | 100 | ℃/W | 1 | |||
| Junction and storage temperature | TJ,Tstg | -55 | 150 | ℃ | 1 |
CAD (KiCad official)
- Symbol:
BD138 - Footprint:
Package_TO_SOT_THT:TO-126-3_Vertical - 3D model: TO-126 (KiCad packages3D, STEP)
- 3D model files:
bd138-etched.step/bd138-etched.glbcarry the MPN laser-etched on the die in a toggleableAdom.LaserEtchgroup (Fusion-ready);bd138.step/bd138.glbare the bare package body.
Provenance
Data extracted from the manufacturer datasheet, not a distributor listing:
- Datasheet: Changjing datasheet (4 pp, sha256
48b0338ef78cd5fc, retrieved 2026-10-27, tier: lcsc) - Extractor: parts-factory
2.0.0/extract_pins 0.3, primaryclaude-haiku-5-5(text), consensusoff(skipped (clean text read)), 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).