BU508DW High-Voltage NPN Transistor

Overview

The BU508DW is a high-voltage, high-speed switching NPN transistor housed in a plastic envelope with an integrated efficiency diode. This component is specifically designed for demanding applications such as horizontal deflection circuits in color television receivers. Its robust construction and high-performance characteristics make it suitable for high-voltage switching applications where reliability and efficiency are critical.

The BU508DW combines high breakdown voltage with fast switching speeds, ensuring optimal performance in deflection circuits and other high-voltage applications. The integrated efficiency diode enhances its functionality by reducing external component count and improving overall system efficiency.

Features

• High Voltage Capability: Designed to handle high-voltage applications with ease.
• Integrated Efficiency Diode: Includes a built-in diode to improve circuit efficiency and reduce external component requirements.
• High-Speed Switching: Optimized for fast switching applications, making it ideal for deflection circuits.
• Robust Construction: Housed in a durable plastic envelope for reliable performance in demanding environments.
• Low Saturation Voltage: Ensures minimal power loss during operation.
• High Current Handling: Capable of managing high current loads, suitable for power applications.

Applications

The BU508DW is primarily used in applications requiring high-voltage switching and fast response times. Key application areas include:

• Horizontal Deflection Circuits: Widely used in color television receivers for horizontal deflection.
• CRT Displays: Suitable for cathode-ray tube (CRT) display systems requiring high-voltage switching.
• Power Supplies: Can be employed in high-voltage power supply circuits.
• Industrial Equipment: Used in industrial systems where high-voltage switching is necessary.
• Electronic Ballasts: Applicable in lighting systems such as electronic ballasts for fluorescent lamps.

Electrical Characteristics

The following table summarizes the key electrical characteristics of the BU508DW under typical operating conditions:

Absolute Maximum Ratings

• Collector-Emitter Voltage (V_CEO): 1500V
• Collector-Base Voltage (V_CBO): 1500V
• Emitter-Base Voltage (V_EBO): 7V
• Collector Current (I_C): 8A
• Base Current (I_B): 2A
• Total Power Dissipation (P_tot): 100W
• Operating Junction Temperature (T_j): -55°C to +150°C

Thermal Characteristics

• Thermal Resistance, Junction to Case (R_th(j-c)): 1.25°C/W
• Thermal Resistance, Junction to Ambient (R_th(j-a)): 62.5°C/W

Dynamic Characteristics

• Turn-On Time (t_on): 1.5µs (typical)
• Turn-Off Time (t_off): 5µs (typical)
• Fall Time (t_f): 1.5µs (typical)

Package Information

The BU508DW is available in a TO-247 plastic package, which provides excellent thermal performance and mechanical robustness. The package dimensions and pin configuration are as follows:

Package Dimensions (TO-247)

• Length: 20.8mm (max)
• Width: 15.6mm (max)
• Height: 5.2mm (max)
• Lead Pitch: 5.45mm (typical)

Pin Configuration

• Pin 1 (Base): Control input for the transistor.
• Pin 2 (Collector): High-voltage and high-current terminal.
• Pin 3 (Emitter): Ground reference and current return path.

Conclusion

The BU508DW is a high-performance NPN transistor designed for high-voltage, high-speed switching applications. Its integrated efficiency diode, robust TO-247 package, and excellent electrical characteristics make it an ideal choice for horizontal deflection circuits in color television receivers and other demanding applications. With its high breakdown voltage and fast switching capabilities, the BU508DW ensures reliable and efficient operation in a variety of high-voltage environments.