General Description

The MAX1544 is a dual-phase, Quick-PWM™, stepdown controller for AMD Hammer™ CPU core supplies. Dual-phase operation reduces input ripple current requirements and output voltage ripple while easing component selection and layout difficulties. The QuickPWM control scheme provides instantaneous response to fast load-current steps. The MAX1544 includes active voltage positioning with adjustable gain and offset, reducing power dissipation and bulk output capacitance requirements.

Features

♦ Dual-Phase, Quick-PWM Controller

♦ ±0.75 VOUT Accuracy Over Line, Load, and

Temperature (1.3V)

♦ Active Voltage Positioning with Adjustable Gain

and Offset

♦ 5-Bit On-Board DAC: 0.675V to 1.55V Output

Adjust Range

♦ Selectable 100kHz/200kHz/300kHz/550kHz

Switching Frequency

♦ 4V to 28V Battery Input Voltage Range

♦ Adjustable Slew-Rate Control

♦ Drives Large Synchronous Rectifier MOSFETs

♦ Selectable Output Overvoltage Protection

♦ Undervoltage and Thermal-Fault Protection

♦ Power Sequencing and Timing

♦ Selectable Suspend Voltage

♦ Soft-Shutdown

♦ Selectable Single- or Dual-Phase Pulse Skipping

Applications

AMD Hammer Desktop or Notebook PCs

Multiphase CPU Core Supply

Voltage-Positioned Step-Down Converters

Servers/Desktop Computers