ON Semiconductor

The NCP1239 is a fixed-frequency current-mode controller featuring the Dynamic Self-Supply. This function greatly simplifies the design of the auxiliary supply and the Vcc capacitor by activating the internal startup current source to supply the controller during start-up, transients, latch, stand-by etc. With a supply range up to 35 V, the controller hosts a jittered 65 or 100-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 minimum level of 26 kHz. As the power further goes down, the part enters skip cycle while limiting the peak current that insures excellent efficiency in light load condition. It features a timer-based fault detection that ensures the detection of overload and an adjustable compensation to help keep the maximum power independent of the input voltage.

The NCP1240 is a new fixed−frequency current−mode controller featuring Dynamic Self−Supply. This function greatly simplifies the design of the auxiliary supply and the VCC capacitor by activating the internal startup current source to supply the controller during start-up, transients, latch, stand-by etc. This device contains a special HV detector which detects the application unplug from the ac input line and triggers the X2 discharge current. This HV structure allows the brown-out detection as well. It features a timer-based fault detection that ensures the detection of overload and an adjustable compensation to help keep the maximum power independent of the input voltage. Due to frequency foldback, the controller exhibits excellent efficiency in light load condition while still achieving very low standby power consumption. Internal frequency jittering, ramp compensation, and a versatile latch input make this controller an excellent candidate for the robust power supply designs. A dedicated Off mode allows to reach the extremely low no load input power consumption via "sleeping" whole device and thus minimize the power consumption of the control circuitry. The NCP1240 differentiates itself from the rest of the fixed frequency flyback controllers with active X2 discharge and HV start up by implementing a Dual-Level Overcurrent protection. For some applications (e.g. limited power supplies), it is necessary that the controller maintains regulation while it has detected a first level of overload. This is to authorize a transient peak power higher than the maximum continuous output power.This product is IEC60950 compliant. Please see the test report and certification in the Conformance report section below.

The NCP12400 is a new fixed−frequency current−mode controller featuring the Dynamic Self−Supply. This function greatly simplifies the design of the auxiliary supply and the VCC capacitor by activating the internal startup current source to supply the controller during start−up, transients, latch, stand−by etc. This device contains a special HV detector which detects the application unplug from the ac input line and triggers the X2 discharge current. This HV structure allows the brown−out detection as well. It features a timer−based fault detection that ensures the detection of overload and an adjustable compensation to help keep the maximum power independent of the input voltage. Due to frequency foldback, the controller exhibits excellent efficiency in light load condition while still achieving very low standby power consumption. Internal frequency jittering, ramp compensation, and a versatile latch input make this controller an excellent candidate for the robust power supply designs. A dedicated Off Mode allows to reach the extremely low no load input power consumption via "sleeping" whole device and thus minimize the power consumption of the control circuitry. In addition, the NCP12400 features a quiet skip mode which lockes the skip frequency below audiable range. This feature greatly reduces audiable noise caused by the switching pulses during skip mode.

The NCP1244 is a new fixed-frequency current-mode controller featuring Dynamic Self-Supply. This function greatly simplifies the design of the auxiliary supply and the Vcc capacitor by activating the internal startup current source to supply the controller during start-up, transients, latch, stand-by etc. This device contains a special HV dtector which detects the application unplug from the AC input line and triggers the X2 discharge current.It features a timer-based fault detection that ensures the detection of overload and an adjustable compensation to help keep the maximum power independent of the input voltage.Due to frequency foldback, the controller exhibits excellent efficiency in light load condition while still achieveing very low standby power consumption. Internal frequency jittering, ramp compensation, and a versatile latch input make this controller an excellent candidate for the robust power supply designs.A dedicated OFF mode allows to reach the extremely low no load input power consumption via sleeping whole device and thus minimze the power consumption of the control circuitry.This product is IEC60950 compliant. Please see the test report and certification in the Conformance report section below.

The NCP1246 is a new fixed-frequency current-mode controller featuring Dynamic Self-Supply. This function greatly simplifies the design of the auxiiary supply and the Vcc capacitor by activating the internal startup current source to supply the controller during start-up, transients, latch, stnad-by etc. This device contains a special HV detector which detects the application unplug from the AC input line and triggers the X2 discharge current. The HV structure also includes brown-out detection circuitry.The NCP1246 features a timer-based fault detection that ensures the detection of overload and an adjustable power compensation to help keep the maximum power independent of the input voltage.Due to frequency foldback, the controller exhibits excellent efficiency in light load condition while still achieving very low standby power consumption. Internal frequency jittering, ramp compensation, and a versatile latch input make this controller an excellent candidate for robust power supply designs.A dedicated off mode allows the SMPS to reach extremely low no load input power consumption when combinded with secondary side contoller NCP4353 or NCP4354. When used together, the SMPS is capable of achieving <10 mW no load input power consumption. The secondary side contoller signals the NCP1246 to enter a sleep mode, minimizing the power consumption of the control circuitry.This product is IEC60950 compliant. Please see the test report and certification in the Conformance report section below.

The NCP1247 is a new fixed-frequency current-mode PWM controller featuring Dynamic Self-Supply. This function greatly simplifies the design of the auxiliary supply and the Vcc capacitor by activating the internal startup current source to supply the controller during start-up, transients, latch, stand-by etc. This device contains a special HV detector which detects the application unplug from the AC input line and triggers the X2 discharge current. The HV structure also includes brown-out detection circuitry.The NCP1247 features a timer-based fault detection that ensures the detection of overload and an adjustable power compensation to help keep the maximum power independent of the input voltage.Due to frequency foldback, the controller exhibits excellent efficiency in light load condition while still achieving very low standby power consumption. Internal frequency jittering, ramp compensation, and a versatile latch input make this controller an excellent candidate for robust power supply designs.A dedicated off mode allows the SMPS to reach extremely low no load input power consumption when combined with secondary side controller NCP4353 or NCP4354. When used together, the SMPS is capable of achieving <10 mW no load input power consumption. The secondary side controller signals the NCP1247 to enter a sleep mode, minimizing the power consumption of the control circuitry. The NCP1247 is very similar in its functionality to the NCP1246. The NCP1247 is designed to get better performance out of systems with synchronous rectification.NCP1247- Adds C & D option for different Brown Out threshold- Enhanced operation with Sync Rec in light load- Increased HV timer- Revised X2 discharge sequenceThis product is IEC60950 compliant. Please see the test report and certification in the Conformance report section below.

The NCP1250 is a highly integrated PWM controller capable of delivering a rugged and high performance offline power supply in a tiny TSOP-6 package. With a supply range up to 28 V, the controller hosts a jittered 65 kHz or 100 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 further goes down, the part enters skip cycle while limiting the peak current. 40W AdapterOver Power Protection (OPP) is a difficult exercise especially when no-load standby requirements drive the converter specifications. The ON proprietary integrated OPP lets you harness the maximum delivered power without affecting your standby performance simply via two external resistors. An Over Voltage Protection input is also combined on the same pin and protects the whole circuitry in case of optocoupler failure or adverse open loop operation.Finally, a timer-based short-circuit protection offers the best protection scheme, letting you precisely select the protection trip point irrespective of a loose coupling between the auxiliary and the power windings.

The NCP1251 is a highly integrated PWM controller capable of delivering a rugged and high performance offline power supply in a tiny TSOP-6 package. With a supply range up to 28 V, the controller hosts a jittered 65 kHz or 100 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 further goes down, the part enters skip cycle while limiting the peak current.Over Power Protection (OPP) is a difficult exercise especially when no-load standby requirements drive the converter specifications. The ON proprietary integrated OPP lets you harness the maximum delivered power without affecting your standby performance simply via two external resistors. A latched Over Voltage Protection (OVP) is combined on the same pin. For ease of implementation, an auto-recovery OVP also monitors the Vcc line. These features offer an efficient protection in case of optocoupler failure or adverse open loop operation.Finally, a timer-based short-circuit protection offers the best protection scheme, letting you precisely select the protection trip point irrespective of a loose coupling between the auxiliary and the power windings.

The NCP12510 is a highly integrated PWM controller capable ofdelivering a rugged and high performance offline power supply in atiny TSOP−6 package. With a voltage supply range up to 35 V, thecontroller hosts a jittered 65−kHz or 100−kHz switching circuitryoperated in peak current mode control. When the power on thesecondary side starts decreasing, the controller automatically foldsback its switching frequency down to a minimum level of 26 kHz. Asthe power further goes down, the part enters skip cycle while limitingthe peak current. The controller has integrated protections such as Over Power Protection (OPP), Over Voltage Protection (OVP) and short-circuit protections. NCP12510 is improved and pin compatible controller based on very popular flyback controller NCP1250.

The NCP1252 controller offers everything needed to build cost effective and reliable ac-dc switching supplies dedicated to ATX power supplies or any forward application. Thanks to the use of an internally fixed timer, NCP1252 detects an output overload without relying on the auxiliary Vcc. A Brown-Out input offers protection against low input voltages and improves the converter safety. Finally, the SOIC-8 package saves PCB space and represents a solution of choice in cost sensitive project.