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BC857-JSM

Public Made by Adom

by adom

JSMSEMI Bipolar (BJT), SOT-23. Pinout cross-checked by two models against the datasheet, KiCad symbol/footprint/3D.

componenttransistors-thyristorsbc857-jsmfactory-2.0.0extractor-text
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Symbol & Footprint

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Datasheet

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Contents

README

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BC857-JSM

JSMSEMI · Bipolar (BJT) · SOT-23

BC857-JSM from JSMSEMI, in a SOT-23. 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 of the PNP transistor; emitter-base voltage limited to -5 V (VEBO) and emitter-base breakdown of -5 V min at IE=-1 µA.
2 EMITTER passive Emitter of the PNP transistor, the terminal that carries the total current of up to 0.1 A collector current.
3 COLLECTOR passive Collector of the PNP transistor; BC857 VCEO is -45 V and VCBO is -50 V, with continuous collector current of -0.1 A max.

Key specifications

Parameter Value
Manufacturer JSMSEMI
Package SOT-23
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 (BC857) VCBO -50 V 1
Collector-Emitter Voltage (BC857) VCEO -45 V 1
Emitter-Base Voltage VEBO -5 V 1
Collector Current -Continuous IC -0.1 A 1
Collector Dissipation PC 250 mW 1
Junction and Storage Temperature Tj,Tstg -65 150 ℃ 1
Collector-base breakdown voltage (BC857) V(BR)CBO -50 V IC=-10μA,IE=0 2
Collector-emitter breakdown voltage (BC857) V(BR)CEO -45 V IC=-10mA,IB=0 2
Emitter-base breakdown voltage V(BR)EBO -5 V IE=-1μA,IC=0 2
Collector cut-off current ICBO -1 -15 nA VCB=-30V,IE=0 2
Emitter cut-off current IEBO -0.1 μA VEB=-5V,IC=0 2
DC current gain (BC857A) hFE 125 250 VCE=-5V,IC=-2mA 2
DC current gain (BC857B) hFE 220 475 VCE=-5V,IC=-2mA 2
DC current gain (BC857C) hFE 420 800 VCE=-5V,IC=-2mA 2
Collector-emitter saturation voltage VCE(sat) -0.65 V IC=-100mA, IB=-5mA 2
Collector-emitter saturation voltage VCE(sat) -0.3 V IC=-10mA, IB=-0.5mA 2
Base-emitter saturation voltage VBE(sat) -0.7 V IC=-10mA, IB=-0.5mA 2
Base-emitter saturation voltage VBE(sat) -0.85 V IC=-100mA, IB=-5mA 2
Base-emitter voltage VBE(on) -0.6 -0.65 -0.75 V IC=-2mA,VCE=-5V 2
Base-emitter voltage VBE(on) -0.82 V IC=-10mA,VCE=-5V 2
Noise figure F 2 10 dB IC=-200uA,VCE=-5V,RS=2kΩ,f=1kHz,B=200Hz 2
Collector capacitance Cc 4.5 pF VCB=-10V,IE=Ie=0,f=1MHz 2
Transition frequency fT 100 MHz VCE=-5V, IC=-10mA, f=100MHz 2

CAD (KiCad official)

  • Symbol: BC857-JSM
  • Footprint: Package_TO_SOT_SMD:SOT-23
  • 3D model: SOT-23 (KiCad packages3D, STEP)
  • 3D model files: bc857-jsm-etched.step / bc857-jsm-etched.glb carry the MPN laser-etched on the die in a toggleable Adom.LaserEtch group (Fusion-ready); bc857-jsm.step / bc857-jsm.glb are the bare package body.

Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

  • Datasheet: JSMSEMI datasheet (6 pp, sha256 7e6ec6519d2121ec, retrieved 2026-10-17, tier: lcsc)
  • Extractor: parts-factory 2.0.0 / extract_pins 0.3, primary claude-sonnet-5-5 (text+vision), consensus claude-opus-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).

Datasheet PDF