ON Semiconductor UC3845BVNG High-Performance Current Mode PWM Controller

The UC3845BVNG from ON Semiconductor is a high-performance current mode pulse-width modulation (PWM) controller that is specifically designed for off-line and DC-to-DC converter applications offering the designer a cost-effective solution with minimal external components. This integrated circuit is tailored for power supply control and provides the necessary features to implement off-line or DC-to-DC fixed-frequency current mode control schemes with a minimal number of external components.

Key Features

• Trimmed Oscillator for Precise Frequency Control: The oscillator frequency is guaranteed to be precise, ensuring consistent performance. This is particularly important for applications where frequency accuracy is critical.
• Oscillator Frequency Guaranteed at 250kHz: The UC3845BVNG operates at a fixed frequency of 250kHz, which is a standard for many power applications, providing an optimal balance between efficiency and component size.
• Current Mode Operation to 500kHz: The controller can operate at a frequency up to 500kHz, allowing for smaller magnetics and filter components, which can be beneficial in compact power supply designs.
• Automatic Feed Forward Compensation: This feature improves the response of the power supply to changes in input voltage without the need for additional external components.
• Pulse-by-Pulse Current Limiting: Enhanced protection is provided by the pulse-by-pulse current limiting feature, which ensures that the power supply remains within safe operating conditions.
• Enhanced Load Response Characteristics: The device is designed to respond quickly to load changes, which is crucial for maintaining voltage regulation and system stability.
• Under-Voltage Lockout with Hysteresis: The built-in under-voltage lockout (UVLO) with hysteresis ensures that the device only operates when the supply voltage is within an acceptable range, protecting the circuit from low-voltage conditions.
• Double Pulse Suppression: This feature prevents the controller from generating multiple pulses on a single cycle, which could lead to erroneous operation or damage to the power switch.

Applications

The UC3845BVNG is ideal for various applications, including:

• Switching power supplies
• Power converters
• Battery chargers
• DC-DC modules
• LED drivers
• Telecommunication equipment

ON Semiconductor's UC3845BVNG offers a robust and flexible solution for your power management needs, ensuring reliability and efficiency in your electronic designs.