The ISL6224 provides a power control and protection, adjustable output voltage required for power chipsets and memory banks in high-performance notebooks and PDAs. This adjustable output voltage range is from 0.9-5.5V. A hysteretic or PWM controller regulates the output voltage from the battery voltage ranging from 4V to 24V. Synchronous rectification and hysteretic operation at light loads over a wide range of high efficiency input voltages and loads. Efficiency is further enhanced by using the RDS(ON) of the MOSFET as the current sensing element. Feed-forward ramp modulation, average current mode control and internal feedback compensation provide fast transients when powering the advanced processing chipset. It is possible to convert in two stages, using the system's 5V voltage at higher frequencies (600KHz) while reducing the size of the output filter. The ISL6224 monitors the output voltage. When a PGOOD (power good) signal is issued, the soft start is complete and the output is within ±10% of the set point. A built-in overvoltage protection prevents the output voltage from rising above the 120% set point. The undervoltage protection latches the chip when the output falls below 70% of its set value after the soft-start sequence is complete. The overcurrent circuit of the PWM controller displays the output current induced by the voltage drop on the lower MOSFET. Optional external current sense can be used for resistors if higher precision sensing techniques are required.