ON Semiconductor Distributor

NCP1255 PWM Controller


ON Semiconductor's PWM Controller offers a high-performance offline power supply


ON Semiconductor's The NCP1255 is a highly integrated PWM controller capable of delivering a rugged and high-performance offline power supply in a SOIC-8 package. With a supply range up to 35 V, the controller hosts a jittered 65 kHz switching circuitry operated in peak current mode control. When the power on the secondary side starts to decrease, the controller automatically folds back its switching frequency down to a minimum level of 26 kHz. As the power goes down further, the part enters skip cycle while freezing the peak current set-point.

To help build rugged converters, the controller features several key protective features, a non-dissipative, over power protection for a constant maximum output current regardless of the input voltage, two latched over-voltage protection inputs, either through a dedicated pin or via the Vcc input and a dual-level auto-recover/latched overload/short-circuit timer.

The controller architecture is designed to authorize a transient peak power excursion when the current set-point hits the limit. At this point, the switching frequency is increased from 65 kHz to 130 kHz until the peak event disappears. The timer duration is then modulated as the converter crosses a peak power excursion mode (long) or undergoes a short circuit (short).
ON Semiconductor's NCP1255 PWM Controller


Digi-Key P/N Manufacturer P/N Description  
NCP1255AD65R2GOSTR-ND NCP1255AD65R2G IC OFF-LINE CNTRLR PWM CM 8SOIC Datasheet
NCP1255AD65R2GOSCT-ND NCP1255AD65R2G IC OFF-LINE CNTRLR PWM CM 8SOIC
NCP1255AD65R2GOSDKR-ND NCP1255AD65R2G IC OFF-LINE CNTRLR PWM CM 8SOIC