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TOSHIBA 2N3A8204-B
Product Introduction
Distribution and semiconductor data identify 2N3A8204-B as a Toshiba switching transistor supplied in different industrial versions. The surface-mount version targets small-signal high-frequency switching, while the TO-220 power version targets switch-mode power supplies, inverters and motor drives.
Detailed content
Technical Specifications
Surface-mount high-speed version:
- Collector-base voltage: 60 V
- Collector-emitter voltage: 50 V
- Emitter-base voltage: 6 V
- Collector current: 0.1 A
- Total power dissipation: 1500 mW
- Operating temperature: -55°C to 150°C
- Package: small surface-mount package
- Characteristics: high-speed switching, low VCE saturation, high current gain, low noise
TO-220 power version:
- Transistor polarity: NPN silicon
- Collector-emitter voltage: 400 V
- Collector current: 20 A continuous
- Power dissipation: 80 W
- Package: TO-220AB
- Characteristics: high-frequency switching, high voltage, high current, suitable for SMPS/inverter/motor drive
Functional Features
The SMD version provides fast switching with minimal board area for signal, audio and low-power dc-dc circuits. The TO-220 version delivers high current and high voltage with external heatsink capability for power conversion.
Material Composition
Both versions use silicon transistor dice. The SMD body uses molded epoxy with plated lead frame. The TO-220 body uses molded plastic with exposed metal tab and copper leads for heatsink mounting.
Structural Characteristics
The SMD device has three miniature surface terminals for base, collector and emitter. The TO-220 device has a through-hole three-lead form with a mounting tab for screw or clip attachment to a heatsink.
Working Principle
A base-emitter current controls collector-emitter conduction in the bipolar transistor. Increasing base drive drives the device into saturation for low-loss switching; removing base drive turns it off. In power circuits, the transistor chops dc voltage to create PWM waveforms for converters, inverters or motor controls.
Installation Requirements
For SMD assembly, use controlled reflow soldering within component rating and avoid thermal shock. For TO-220, mount on a flat heatsink with insulating pad or anodized insulator where electrical isolation is required. Apply specified screw torque and keep PCB creepage distances adequate for the working voltage.
Usage Notes
Never exceed the voltage, current or power rating of the selected version. Use base-current limiting resistors or gate/drive circuits suitable for the device. For TO-220 power use, monitor junction temperature and maintain heatsink airflow. For SMD use, avoid overload that exceeds 1500 mW package dissipation.
