Off lining switching power supply solution of OnSemiNCP107515W low power consumption

The NCP1072/NCP1075 products integrate a fixed frequency current mode controller with a 700 V MOSFET. Available in a PDIP 7 or SOT 223 package, the NCP1072/5 offer a high level of integration, including soft start, frequency jittering, short circuit protection, cycle skipping, a maximum peak current set point, ramp compensation, and a dynamic self-supply, eliminating the need for an auxiliary winding. Unlike other monolithic solutions, the NCP1072/5 operates quietly; during nominal load conditions, the device switches at one of the available frequencies: 65 kHz, 100 kHz, or 130 kHz. When the output power demand decreases, the IC automatically enters frequency foldback mode, maintaining excellent efficiency at light loads. As power demand diminishes further, it transitions into skip mode to reduce standby consumption to a no-load condition. Protection features include a timer for overload or short circuit detection, overvoltage protection with auto recovery, and AC input line voltage detection. For enhanced standby performance, connecting an auxiliary winding halts the DSS operation, helping to lower input power consumption to below 50 mW at high line.

The NCP1072/NCP1075 series is designed for high-efficiency power supply applications, particularly in scenarios where space and thermal management are critical. The integrated 700 V MOSFET allows for robust performance in high-voltage environments, making it suitable for a variety of applications including adapters and chargers. The fixed frequency current mode control enhances loop stability and improves transient response, contributing to a reliable output voltage regulation.

The soft start feature reduces inrush current during startup, preventing potential damage to the circuit components and ensuring a smooth power-up sequence. Frequency jittering aids in minimizing electromagnetic interference (EMI), which is crucial for compliance with regulatory standards in consumer electronics.

The skip cycle mode is particularly advantageous in applications with varying load conditions, as it allows the power supply to operate efficiently at low power demands without wasting energy. This capability is complemented by the frequency foldback mode, which dynamically adjusts the switching frequency based on the output load, further enhancing efficiency during light load conditions.

In terms of protection mechanisms, the overload timer is a vital feature that ensures the device can detect and respond to fault conditions, thereby safeguarding the circuit against damage. The overvoltage protection with auto recovery is essential for maintaining output voltage within specified limits, and the AC input line voltage detection feature ensures the device operates safely across a wide range of input voltages.

The option to connect an auxiliary winding is a significant advantage, as it not only aids in reducing standby power consumption but also enhances the overall efficiency of the power supply design. This feature allows for a more compact design while ensuring compliance with energy efficiency standards, making the NCP1072/NCP1075 series an excellent choice for modern power supply designs.The NCP1072/NCP1075 products integrate a fixed frequency current mode controller with a 700 V MOSFET. Available in a PDIP 7 or SOT 223 package, the NCP1072/5 offer a high level of integration, including soft start, frequency jittering, short circuit protection, skip cycle, a maximum peak current set point, ramp compensation, and a Dynamic Se

lf Supply eliminating the need for an auxiliary winding. Unlike other monolithic solutions, the NCP1072/5 is quiet by nature: during nominal load operation, the part switches at one of the available frequencies 65, 100 or 130 kHz. When the output power demand diminishes, the IC automatically enters frequency foldback mode and provides excellent efficiency at light loads.

When the power demand reduces further, it enters into a skip mode to reduce the standby consumption down to a no load condition. Protection features include: a timer to detect an overload or a short circuit event, Overvoltage Protection with auto recovery and AC input line voltage detection.

For improved standby performance, the connection of an auxiliary winding stops the DSS operation and helps to reduce input power consum ption below 50 mW at high line. 🔗 External reference