The 90 W demo board demonstrates the wide range of
features found in the NCP1651. It provides an 18.5 V, 4.86 A
isolated output, foldback current limit which is ideal for
low?cost battery charger and notebook adaptor applications.
This unit will provide an isolated 18.5 V output from an
input source with a frequency range from 47 Hz to 63 Hz,
and a voltage range of 90 Vrms to 265 Vrms. It is fully
self?contained and includes an internal high voltage startup
circuit, and bias supply that operates off of the Flyback
transformer auxiliary winding.
In addition to excellent power factor, this chip offers fixed
frequency operation in continuous and discontinuous modes
of operation. It has a wide variety of protection features,
including instantaneous current limiting, average current
limiting, and an accurate secondary side power limit.
Features
? Fixed Frequency Operation
? Operation Over the Universal Input Range
? Multiple Protection Schemes
? Single Power Stage with Isolated Output
? Startup and Bias Circuits Included