BY255 1300V 3A Fast Recovery Diode DO-27

BY255 1300V 3A Fast Recovery Diode DO-27 is a robust semiconductor device designed for use in power supply circuits, inverters, and high-frequency rectification stages where both high voltage handling and fast switching are critical. Its primary function is to prevent current from flowing in the wrong direction while minimizing energy loss during the transition from the conducting to the blocking state. With an impressive 1300V reverse voltage rating and a 3A forward current capacity, this diode reliably handles demanding loads. Crucially, its fast recovery time makes it far superior to standard rectifier diodes in switching applications, allowing circuits to operate at higher frequencies with improved efficiency and reduced heat generation. Engineers depend on the BY255 to maintain the integrity and performance of their high-speed power conversion designs.

Key Features:

• High Reverse Voltage: Offers a non-repetitive peak reverse voltage (V_RRM) of 1300V, providing a large safety margin in circuits operating directly from 120V or 240V AC mains.
• Fast Recovery Time: The short reverse recovery time (t_rr) minimizes switching losses and enables operation in high-frequency power supply and chopper circuits.
• High Current Capacity: Handles an average forward current (I_F(AV)) of 3A, making it suitable for moderate-power rectification tasks.
• Low Forward Voltage Drop: Features a low forward voltage (V_F) to reduce power dissipation and improve overall circuit efficiency.
• Hermetically Sealed Package: The robust DO-27 axial-leaded glass package ensures long-term reliability and resistance to environmental stress.

Technical Specifications:

• Peak Repetitive Reverse Voltage (V_RRM): 1300 V
• Average Forward Current (I_F(AV)): 3 A
• Forward Voltage Drop (V_F): Max 1.3 V @ 3 A
• Reverse Recovery Time (t_rr): Max 500 ns (Nanoseconds)
• Maximum Operating Temperature: 175 °C
• Mounting Style: Through-hole

Mechanical Specifications:

• Package Type: DO-27 (Also known as DO-201AD)
• Lead Type: Axial leads for through-hole mounting or soldering.
• Body Material: Hermetically sealed glass casing.

Dimensions:

• Body Diameter: Approx. 5.3 mm
• Body Length: Approx. 9.5 mm
• Lead Diameter: Approx. 1.2 mm

Pinout and Wiring:

• Anode (A): The positive terminal, typically indicated by the end *without* the colored band. Current flows *into* the Anode.
• Cathode (K): The negative terminal, indicated by the colored band (usually white or silver). Current flows *out* of the Cathode during forward bias.
• Wiring Note: Always install the diode so the cathode band is positioned to block reverse current flow in your circuit. The colored band marks the output side (negative side) in a rectifier application.

Datasheet Reference:

• Download Datasheet

Commonly Used in:

• Switched-Mode Power Supplies (SMPS): Used for high-efficiency rectification in the secondary stage of the power supply.
• Lighting Ballasts: Essential components in compact fluorescent (CFL) and LED driver circuits for AC-to-DC conversion.
• Motor Control: Implementing “free-wheeling” or “snubber” circuits to protect switching components from inductive spikes.

Applications:

• AC/DC Rectification: Efficiently converting high-voltage AC input into pulsating DC power.
• Inverters and Converters: Serving as the fast-acting rectification element in DC-DC and DC-AC converters.
• Protection Circuits: Preventing voltage reversal and providing surge suppression in sensitive equipment.

Equivalent Models:

• UF5408: A popular 3A ultra-fast recovery rectifier with a similar voltage rating (1000V).
• HER308: Another fast-recovery diode offering 3A current but typically a lower reverse voltage rating.

Package Includes:

• 1 x BY255 1300V 3A Fast Recovery Diode DO-27