component
BC857-JSM
Public Made by Adomby adom
JSMSEMI Bipolar (BJT), SOT-23. Pinout cross-checked by two models against the datasheet, KiCad symbol/footprint/3D.
main
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.glbcarry the MPN laser-etched on the die in a toggleableAdom.LaserEtchgroup (Fusion-ready);bc857-jsm.step/bc857-jsm.glbare 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, primaryclaude-sonnet-5-5(text+vision), consensusclaude-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).
# 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](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8603613821831696384) (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](docs/bc857-jsm-datasheet.pdf)