The packaged NCP1200 in a SOIC-8 or PDIP-8 package represents a major leap towards ultra-small switching power supplies. Thanks to a brand new concept, the circuit allows to implement a complete offline battery charger or few external standby SMPS components. Additionally, integrated output short-circuit protection allows designers to build an extremely low-cost AC-DC adapter associated with a simplified feedback scheme. With an internal structure operating at a fixed 40 kHz, 60 kHz or 100 kHz, the controller drives low gate charge exchange devices such as IGBTs or MOSFETs and therefore requires a very small operating power. Thanks to current-mode control, the NCP1200 dramatically simplifies the design of reliable and inexpensive off-line converters with extremely low acoustic generation and inherent pulse-by-pulse control. When the current setpoint is lower than the setpoint, for example: when the output power demand decreases, the IC automatically enters skip cycle at light load mode and provides excellent efficiency. Because this occurs at low peak currents, no noise occurs. Finally, the IC provides DC voltage, eliminating the need for auxiliary windings. This feature ensures operation in the presence of low output voltages or shorts.

Features • No auxiliary winding operation • Internal output short circuit protection • Very low no-load standby power consumption • Current mode skip cycling capability • Internal leading leading edge blanking • 250 mA peak current source/sink capability • Internal fixed frequency at 40k kHz, 60 kHz, 100 kHz • Direct optocoupler connection • Built-in frequency jitter to reduce EMI • SPICE model for transient and AC analysis • Internal temperature shutdown • Lead-free package available