Dual Mobile-Friendly PWM Controller with DDR Memory Option
The ISL6225 dual PWM controller delivers high efficiency and tight regulation from two voltage regulating synchronous buck DC/DC converters. The ISL6225 PWM power supply controller was designed especially for DDR DRAM, SDRAM, and graphic chipset applications in high performance desknote PCs, notebook PCs, sub-notebook PCs, and PDAs.
FEATUREs
• Provides regulated output voltage in the range of 0.9V-5.5V
- High efficiency over wide load range
- Synchronous buck converter with hysteretic operation at
light load
- Inhibit Hysteretic mode on one, or both channels
• Complete DDR memory power solution
- VTT tracks VDDQ/2
- VDDQ/2 buffered reference output
• No current-sense resistor required
- Uses MOSFET rDS(ON)
- Optional current-sense resistor for precision overcurrent
• Under-voltage lock-out on VCC pin
• Dual input voltage mode operation
- Operates directly from battery 5V to 24V input
- Operates from 3.3V or 5V system rail
- VCC from 5V only
• Excellent dynamic response
- Combined voltage feed-forward and average current
mode control
• Power-good signal for each channel
• 300kHz switching frequency
- 180° channel to channel phase operation for reduced input
ripple when not in DDR mode
- 0° channel to channel phase operation in DDR mode for
reduced channel interference
- 90° channel to channel phase operation for reduced input
ripple in DDR mode when VIN is at GND.
• Pb-Free Available (RoHS Compliant)
APPLICATIONs
• Mobile PCs
• PDAs
• Hand-held portable instruments