The KA5M02659R, manufactured by Fairchild/ON Semiconductor, is a self-oscillating Power Switch designed for offline power supplies. It integrates a SenseFET and a current mode PWM (Pulse Width Modulation) controller in a single package. This integration helps to minimize external components and simplifies power supply design, making it a cost-effective solution for various applications requiring efficient and compact power sources. It operates using Fixed Frequency Off-Line Switch technology.

Applications

• Power Adapters: Used in AC-DC adapters for mobile phones, tablets, and other portable devices.
• Open-Frame Power Supplies: Found in low-power open-frame power supplies for various electronic devices.
• Auxiliary Power Supplies: Implemented as auxiliary power supplies in larger electronic systems.
• DVD Players/Recorders: Used in the power supply sections of DVD players and recorders.
• Set-Top Boxes: Provides the power for set-top boxes.

Features

• Internal Avalanche Rugged SenseFET: Integrates a robust SenseFET, eliminating the need for an external MOSFET.
• Fixed Frequency PWM Controller: Provides stable and predictable operation.
• Built-in Soft-Start: Reduces stress on components during startup.
• Over Voltage Protection (OVP): Protects the power supply and connected devices from overvoltage conditions.
• Over Current Protection (OCP): Protects the power supply from overcurrent conditions.
• Thermal Shutdown Function: Shuts down the device in case of overheating.
• Under Voltage Lockout (UVLO): Prevents operation at low input voltages.

Benefits

• Simplified Design: Integration reduces component count and simplifies power supply design.
• Cost-Effective Solution: Single-chip solution reduces overall system cost.
• Improved Reliability: Built-in protection features enhance reliability.
• Compact Size: Integration allows for smaller power supply designs.
• High Efficiency: PWM control and SenseFET technology contribute to efficient power conversion.

Additional Details

The KA5M02659R typically operates with a fixed switching frequency. The datasheet specifies the operating frequency, voltage ratings, and current limits. The device typically comes in a DIP or a similar through-hole package. The soft-start feature gradually increases the pulse width of the PWM signal during startup, reducing inrush current and preventing voltage overshoot. The OVP circuit monitors the output voltage and shuts down the device if it exceeds a certain threshold. The OCP circuit limits the output current to prevent damage from overload conditions. Proper heatsinking may be required, depending on the operating conditions and output power level. The '0265' part of the identifier usually relates to the current/power capability of the device. The device's datasheet should always be consulted for detailed specifications and application guidelines.