ACPI Regulator/Controller for Dual Channel DDR Memory Systems
The ISL6548A provides a complete ACPI compliant power solution for up to 4 DIMM dual channel DDR/DDR2 Memory systems. Included are both a synchronous buck controller to supply VDDQ during S0/S1 and S3 states. During S0/S1 state, a fully integrated sink-source regulator generates an accurate (VDDQ/2) high current VTT voltage without the need for a negative supply. A second PWM controller, which requires external MOSFET drivers, is available for regulation of the GMCH Core voltage. A sink/source LDO controller is also integrated for the CPU/GMCH VTT termination voltage regulation. Another LDO is available for the ICH7 voltage.
FEATUREs
• Generates 5 Regulated Voltages
- Synchronous Buck PWM Controller for DDR VDDQ
- 3A Integrated Sink/Source Linear Regulator with
Accurate VDDQ/2 Divider Reference for DDR VTT
- PWM Regulator for GMCH Core
- Sink/Source LDO Regulator for CPU/GMCH VTT
Termination
- LDO Regulator for ICH7
• ACPI Compliant Sleep State Control
• Glitch-free Transitions During State Changes
• VDDQ PWM Controller Drives Low Cost N-Channel
MOSFETs
• 250kHz Constant Frequency Operation
- Both PWM Controllers are Phase Shifted 180°
• Tight Output Voltage Regulation
- All Outputs: ±2% Over Temperature
• Fully-Adjustable Outputs with Wide Voltage Range: Down
to 0.8V supports DDR and DDR2 Specifications
• Simple Single-Loop Voltage-Mode PWM Control Design
• Fast PWM Converter Transient Response
• Under and Overvoltage Monitoring
• OCP on the VDDQ Switching Regulator
• Integrated Thermal Shutdown Protection
• Pb-Free Plus Anneal Available (RoHS Compliant)
APPLICATIONs
• Single and Dual Channel DDR Memory Power Systems in
ACPI Compliant PCs
• Graphics Cards - GPU and Memory Supplies
• ASIC Power Supplies
• Embedded Processor and I/O Supplies
• DSP Supplies