Topologie | Sonstige Topologie |
Schaltfrequenz | 100-1000 kHz |
IC-Revision | 1 |
The NCP12700 is a fixed frequency, peak current mode, PWMcontroller containing all of the features necessary for implementing single−ended power converter topologies. The device features a high voltage startup capable of operating over a wide input range and supplying at least 15 mA to provide temporary bias to VCC during system startup. The device contains a programmable oscillator capable of operating from 100 kHz to 1 MHz and integrates slopecompensation to prevent subharmonic oscillations. The controller offers an adjustable soft−start, input voltage UVLO protection, and an adjustable Over−Power Protection circuit which limits the total power capability of the circuit as the input voltage increases, easing the system thermal design. The UVLO pin also features a shutdown comparator which allows for an external signal to disable switching and bring the controller into a low quiescent state.The NCP12700 contains a suite of protection features including cycle−by−cycle peak current limiting, timer−based overload protection, and a FLT pin which can be interfaced with an NTC and an auxiliary winding to provide system thermal protection and output over−voltage protection. All protection features place the device into a low quiescent fault mode and recovery from fault mode is dependent on the device option.