ISL6224
Single Output Mobile-Friendly PWM Controller
Not Recommended for New Designs.
Recommended Replacement Part ISL6269.
Typical Diagram
Key Features
- Adjustable output voltgage: 0.9-5.5V
- High efficiency over wide load range
- Higher efficiency in hysteretic mode at light load
- Lossless current sense scheme
- Uses MOSFET's rDS(ON)
- Optional current sense method higher precision
- Supply operation mode
- Wide VIN range: 4V-24V
- Single 5V system rail
- Input undervoltage lock-out on VCC pin(UVLO)
- Excellent dynamic response
- Combined voltage feed-forward and current mode control
- Power-Good indicator
- 300/600kHz switching frequency
- Thermal shut-down
- Pb-Free Available (RoHS Compliant)
Description
The ISL6224 provides power control and protection for a single, adjustable output voltage required to power chip-sets and memory banks in high-performance notebooks and PDAs. This output voltage is adjustable in the range from 0.9-5.5V.
The hysteretic or PWM controller regulates the output voltage from battery voltages ranging from 4V to 24V. Synchronous rectification and hysteretic operation at light loads contribute to a high efficiency over a wide range of input voltages and loads. Efficiency is even further enhanced by using MOSFET's rDS(ON) as a current sense component. Feed-forward ramp modulation, average current mode control and internal feed-back compensation provide fast and firm handling of transients when powering advanced chip sets.
Two-stage conversion using system 5V voltage is possible at a higher frequency (600kHz) to minimize the output filter size.
The ISL6224 monitors the output voltage. A PGOOD (power good) signal is issued when soft-start is completed and the output is within ±10% of the set point.
A built-in overvoltage protection prevents output voltage from going above 120% of the set point. Undervoltage protection latches the chip off when the output drops below 70% of its setting value after soft-start sequence is completed. The PWM controller's overcurrent circuitry monitors the output current by sensing the voltage drop across the lower MOSFET. If higher precision sense technique is required, an optional external current-sense resistor may be used.
Applications
- Mobile PCs
- Graphic cards
- Hand-held portable instruments
