General Description
The RT9244 is a multi-phase buck DC/DC controller integrated with all control functions for GHz CPU VRM. The RT9244 controls 2, 3 or 4 buck switching stages operating in interleaved phase set automatically. The multiphase architecture provides high output current while maintaining low power dissipation on power devices and low stress on input and output capacitors. The high equivalent operating frequency also reduces the component dimension and the output voltage ripple in load transient.

Features
• Multi-Phase Power Conversion with Automatic Phase Selection
• K8 DAC Output with Active Droop Compens-ation for Fast Load Transient
• Smooth VCORE Transition at VID Jump
• Power Stage Thermal Balance by RDS(ON) Current Sense
• Hiccup Mode Over-Current Protection
• Programmable Switching Frequency (50kHz to 400kHz per Phase), Under-Voltage Lockout and Soft-Start
• High Ripple Frequency Times Channel Number
• RoHS Compliant and 100% Lead (Pb)-Free

Applications
• AMD® AthlonTM 64 and OpteronTMProcessors Voltage Regulator
• Low Output Voltage, High Current DC-DC Converters
• Voltage Regulator Modules