AP3968

Preliminary Datasheet Primary Side Power Switcher for Off-line SMPS General Description The AP3968/69/70/70S consists of a primary side regulation controller and a high voltage transistor, and is specially designed for off-line power supplies within 12W output power. Typical applications include adapter for ADSL and auxiliary supplies. The AP3968/69/70/70S operates at pulse frequency modulation (PFM), and provides accurate constant voltage, constant current (CV/CC) regulation without requiring an opto-coupler and secondary control circuitry. It has internal cable compensation function for tight constant voltage regulation. The AP3968/69/70/70S solution has fewer component numbers, smaller size, and lower total cost. The AP3968 is packaged in SOIC-7. The AP3969/70/70S is packaged in DIP-7 and DIP-8. AP3968/69/70/70S Features Primary Side Control for Eliminating Opto-coupler and Secondary CV/CC Control Circuitry Built-in NPN Transistor with 700VCBO Low Start-up Current: 0.2µA (Typ.) Internal Output Cable Voltage Drop Compensation Random Frequency Modulation for Low EMI Short Circuit Protection Low Total Cost Solution Output Power Range (Note 1): AP3968 for 5W Adapter AP3969 for 7.5W Adapter AP3970 for 12W Adapter AP3970S for 10W Adapter Note 1: Typical continuous power in a non-ventilated enclosed adapter measured at 50ºC ambient. Applications Chargers Adapters Set Top Boxes Auxiliary Supplies DVD LED Driver SOIC-7 DIP-7 DIP-8 Figure 1. Packa...