The NCP1015 integrates a fixed−frequency current−mode controller and a 700 V voltage MOSFET. Housed in a PDIP−7 or SOT−223 package, the NCP1015 offers everything needed to build a rugged and low−cost power supply, including soft−start, frequency jittering, short−circuit protection, skip−cycle, a maximum peak current set−point, and a Dynamic Self−Supply (no need for an auxiliary winding).
Unlike other monolithic solutions, the NCP1015 is quiet by nature. During nominal load operation, the part switches at one of the available frequencies (65−100 kHz). When the current set−point falls below a given value, e.g. the output power demand diminishes, the IC automatically enters the so−called skip cycle mode and provides excellent efficiency at light loads. Because this occurs at typically 0.25 of the maximum peak value, no acoustic noise takes place. As a result, standby power is reduced to the minimum without acoustic noise generation.
Short−circuit detection takes place when the feedback signal fades away e.g. untrue short−circuit or broken optocoupler cases. Finally, soft−start and frequency jittering further easeieeasesesigner's task to quickly develop low−cost and robust offline power supplies. For improved standby performance, the connection of an auxiliary winding stops the DSS operation and helps to consume less than 100 mW at a high line.
