component

MMSTA42

Public Made by Adom

by adom

Changjing Bipolar Transistors - BJT, SOT-323. Pinout cross-checked by two models against the datasheet, KiCad symbol/footprint/3D.

componenttriode-mos tube-transistormmsta42factory-2.0.0extractor-text

Verified MMSTA42

by Ray · last 4 Nov 2026 · 1 record · files match
SymbolFootprint3D modelPins

Verification log 1 record

4 Nov 2026RayPublished by the parts factory: tier lcsc, 3 pinsfiles match
SymbolFootprint3D modelPinsfor all variants
  • ✓component-page-verify: PASS
  • ✓cad_props: Datasheet, MPN and distributor properties match page.json
  • ✓component: MMSTA42 · SOT-323 · 3 pins
  • ✓copper: 3 copper pads, none touching another net
  • ✓datasheet: all 3 pin names found in the 4-page datasheet
  • •distributor (warn): no ['digikey', 'mouser'] number
  • ✓family: SOT-323_SC-70
  • ✓files: 7 declared files present
  • ✓hero: docs/hero.png 4000x2500
  • ✓lbr: OK: /tmp/cpv-mzttkrwr/x.lbr is a valid EAGLE .lbr with complete deviceset
  • ✓license: CC-BY-SA-4.0
  • ✓models_3d: 2 records
  • ✓package_fit: height and body within the datasheet's package drawing (datasheet p.3)
  • ✓pads: 3 pins = 3 pads
  • ✓pose: 2 STEP(s) Z-up, seated, centred
  • ✓symbol: 3 pins agree
  • ✓visibility: public, source open
Evidencedatasheet
Verified files✓ mmsta42.kicad_sym✓ mmsta42.kicad_mod✓ mmsta42.step
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Generated by kicad-footprint-generator · KiCad file format 20260206
Name Last commit message Last updated
docs Publish 0.1.0 · Ray 2d ago
viewers mmsta42: viewers · Ray 2d ago
mmsta42-etched.glb Publish 0.1.0 · Ray 2d ago
mmsta42-etched.step mmsta42: factory component page (tier=lcsc) · Ray 2d ago
mmsta42-hero.glb mmsta42: hero GLB from the etched model (keeps the MPN mark) · Ray 2d ago
mmsta42-hero.overlay.json Publish 0.1.0 · Ray 2d ago
mmsta42.glb Publish 0.1.0 · Ray 2d ago
mmsta42.kicad_mod Publish 0.1.0 · Ray 2d ago
mmsta42.kicad_sym Publish 0.1.0 · Ray 2d ago
mmsta42.lbr Publish 0.1.0 · Ray 2d ago
mmsta42.step Publish 0.1.0 · Ray 2d ago
package.json Publish 0.1.0 · Ray 2d ago
page.json Set visibility: public · Ray 2d ago
README.md Publish 0.1.0 · Ray 2d ago
verification.json Verified: Published by the parts factory: tier lcsc, 3 pins · Ray 2d ago

MMSTA42

Changjing · Bipolar Transistors - BJT · SOT-323

MMSTA42 from Changjing, in a SOT-323. 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 passive Base terminal of the NPN transistor; the datasheet limits the emitter-base voltage to VEBO 5 V and the emitter-base breakdown to V(BR)EBO 5 V.
2 EMITTER passive Emitter terminal of the NPN transistor; the datasheet limits the emitter-base voltage to VEBO 5 V maximum.
3 COLLECTOR passive Collector terminal of the NPN transistor; the datasheet rates VCBO 300 V, VCEO 300 V, IC 0.2 A continuous and ICM 0.5 A pulsed.

Key specifications

Parameter Value
Manufacturer Changjing
Package SOT-323
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 300 V IC=100μA,IE=0 1
Collector-emitter breakdown voltage V(BR)CEO 300 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 0.25 μA VCB=200V,IE=0 1
Emitter cut-off current IEBO 0.1 μA VEB=5V,IC=0 1
DC current gain hFE(1) 60 VCE=10V,IC=1mA 1
DC current gain hFE(2) 100 200 VCE=10V,IC=10mA 1
DC current gain hFE(3) 75 VCE=10V,IC=30mA 1
Collector-emitter saturation voltage VCE(sat) 0.2 V IC=20mA,IB=2mA 1
Base-emitter saturation voltage VBE(sat) 0.9 V IC=20mA,IB=2mA 1
Transition frequency fT 50 MHz VCE=20V,IC=10mA,f=30MHz 1
Collector-base voltage VCBO 300 V Ta=25℃ 1
Collector-emitter voltage VCEO 300 V Ta=25℃ 1
Emitter-base voltage VEBO 5 V Ta=25℃ 1
Collector current -continuous IC 0.2 A Ta=25℃ 1
Collector current -pulsed ICM 0.5 A Ta=25℃ 1
Collector power dissipation PC 0.3 W Ta=25℃ 1
Operation junction and storage temperature range TJ,Tstg -55 150 ℃ 1
Thermal resistance from junction to ambient RθJA 417 ℃/W 1

CAD (KiCad official)

  • Symbol: MMSTA42
  • Footprint: Package_TO_SOT_SMD:SOT-323_SC-70
  • 3D model: SOT-323 (KiCad packages3D, STEP)
  • 3D model files: mmsta42-etched.step / mmsta42-etched.glb carry the MPN laser-etched on the die in a toggleable Adom.LaserEtch group (Fusion-ready); mmsta42.step / mmsta42.glb are the bare package body.

Provenance

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

  • Datasheet: Changjing datasheet (4 pp, sha256 001b875a333175a5, retrieved 2026-11-04, tier: lcsc)
  • Extractor: parts-factory 2.0.0 / extract_pins 0.3, primary claude-haiku-5-5 (text), consensus claude-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).

Datasheet PDF