FAN5231

www.fairchildsemi.com FAN5231 Precision Dual PWM Controller And Linear Regulator for Notebook CPUs Features Provides 3 Regulated Voltages – Microprocessor core (SpeedStep™-enabled) – Microprocessor I/O – Microprocessor Clock Generator High Efficiency Over Wide Load Range Not Dissipative Current-Sense Scheme – Uses MOSFET’s R DS(ON) – Optional Current-Sense Resistor for Precision Overcurrent Adaptive Dead Time Drivers for N-Channel MOSFETs Operates from +5V, +3.3V and Battery (5.6-24V) Inputs Precision Core Voltage Control: – Remote “Kelvin” Sensing – Summing Current-Mode Control – On-Chip Mode-Compensated “Droop” for Optimum Transient Response and Lower Processor Power Dissipation TTL-Compatible 5-Bit Digital Output Voltage Selection – Wide Range - 0.925VDC to 1.3VDC in 25mV Steps, and from 1.3VDC to 2.0VDC in 50mV Steps – Programmable “On-the-Fly” VID code change with customer programmable slew rate and 100ms settling time Power-Good Output Voltage Monitor No negative Core and I/O voltage on turn-off Over-Voltage, Under-Voltage and Over-Current Fault Monitors 300kHz Fixed Switching Frequency Thermal Shut-Down Applications Converters for Mobile Dual-Mode CPUs Web Tablets Internet Appliances +V IN PWM 2 V OUT2 I/ O CONTROLLER PWM 1 CONTROLLER V OUT1 CORE +V IN 3.3V V OUT3 CPU CLK LI NEAR REGULATOR VI D CODE FAN5231 Figure 1. Simplified Power System Diagram REV. 1.1.1 8/15/01 FAN5231 Description The FAN5231 is a highly integrated power ...