component
BC857T
Public Made by Adomby adom
Changjing Bipolar (BJT), SOT-523. Pinout cross-checked by two models against the datasheet, KiCad symbol/footprint/3D.
3D Model
Open in new tab ↗
Loads when you scroll to it. Unloads after 5 minutes in the background.
Symbol & Footprint
Schematic Symbol
Open full view ↗Loads when you scroll to it. Unloads after 5 minutes in the background.
PCB Footprint
Open full view ↗Loads when you scroll to it. Unloads after 5 minutes in the background.
Datasheet
Open in new tab ↗Loads when you scroll to it. Unloads after 5 minutes in the background.
README
markdownBC857T
Changjing · Bipolar (BJT) · SOT-523
BC857T from Changjing, in a SOT-523. 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 | BASE | input | Base terminal of the BC857T PNP transistor; the datasheet's absolute emitter-base voltage rating (VEBO) is -6 V. |
| 2 | EMITTER | passive | Emitter terminal of the BC857T PNP transistor; the datasheet's absolute emitter-base voltage rating (VEBO) is -6 V. |
| 3 | COLLECTOR | passive | Collector terminal of the BC857T PNP transistor; the datasheet gives a collector-emitter voltage (VCEO) of -45 V and continuous collector current of -0.1 A. |
Key specifications
| Parameter | Value |
|---|---|
| Manufacturer | Changjing |
| Package | SOT-523 |
| 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 breakdown voltage | V(BR)CBO | -50 | V | IC= -10µA, IE=0 | 1 | ||
| Collector-emitter breakdown voltage | V(BR)CEO | -45 | V | IC= -10mA, IB=0 | 1 | ||
| Emitter-base breakdown voltage | V(BR)EBO | -6 | V | IE= -1µA, IC=0 | 1 | ||
| Collector cutoff current | ICBO | -15 | nA | VCB=-30V | 1 | ||
| DC current gain | hFE | 125 | 800 | VCE=-5V, IC=-2mA | 1 | ||
| Collector-emitter saturation voltage | VCE(sat) | -0.3 | V | IC=-10mA, IB=-0.5 mA | 1 | ||
| Collector-emitter saturation voltage | VCE(sat) | -0.65 | V | IC=-100mA, IB=-5 mA | 1 | ||
| Base-emitter saturation voltage | VBE(sat) | -0.7 | V | IC=-10mA, IB=-0.5 mA | 1 | ||
| Base-emitter saturation voltage | VBE(sat) | -0.9 | V | IC=-100mA, IB= -5 mA | 1 | ||
| Base-emitter voltage | VBE(on) | -600 | -750 | mV | VCE= -5V, IC= -2mA | 1 | |
| Base-emitter voltage | VBE(on) | -820 | mV | VCE= -5V, IC= -10mA | 1 | ||
| Transition frequency | fT | 100 | MHz | VCE= -5 V, IC= -10mA, f=100MHz | 1 | ||
| Collector output capacitance | Cob | 4.5 | pF | VCB=-10V, f=1MHz | 1 | ||
| Noise figure | NF | 10 | dB | VCE=-5V, IC=-0.2mA, f=1kHz, RS=2kΩ, BW=200Hz | 1 | ||
| Operation junction and storage temperature range | TJ,Tstg | -55 | 150 | ℃ | 1 | ||
| Collector-base voltage | VCBO | -50 | V | 1 | |||
| Collector-emitter voltage | VCEO | -45 | V | 1 | |||
| Emitter-base voltage | VEBO | -6 | V | 1 | |||
| Collector current, continuous | IC | -0.1 | A | 1 | |||
| Collector power dissipation | PC | 150 | mW | 1 |
CAD (KiCad official)
- Symbol:
BC857T - Footprint:
Package_TO_SOT_SMD:SOT-523 - 3D model: SOT-523, generated from the KiCad footprint (body from the F.Fab outline, terminals on the pads, 0.8 mm nominal SOT-523 height). Neither the vendor nor KiCad ships a 3D model for this package, so the dimensions are nominal, not the manufacturer's CAD (STEP)
- 3D model files:
bc857t-etched.step/bc857t-etched.glbcarry the MPN laser-etched on the die in a toggleableAdom.LaserEtchgroup (Fusion-ready);bc857t.step/bc857t.glbare the bare package body.
Provenance
Data extracted from the manufacturer datasheet, not a distributor listing:
- Datasheet: Changjing datasheet (4 pp, sha256
acd5b537693be1c2, retrieved 2026-10-17, 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).