ISL6223

The ISL6223 multi-phase PWM control IC together with its companion gate drivers, the HIP6601, HIP6602 or HIP6603
and Intersil MOSFETs provides a precision voltage regulation system for advanced mobile microprocessors. A single-stage regulator that directly converts a battery voltage to a microprocessor core voltage can be designed when high voltage drivers are employed. Multiphase power conversion is a marked departure from earlier single phase converter configurations previously employed to satisfy the ever increasing current demands of modern microprocessors.Multi-phase converters, by distributing the power and load current, result in smaller and lower cost transistors with fewer input and output capacitors. These reductions accrue from the higher effective conversion frequency with higher frequency ripple current due to the phase interleaving process of this topology. For example, a two phase converter operating at 350kHz will have a ripple frequency of 700kHz.Moreover, greater converter bandwidth of this design results in faster response to load transients.

Outstanding features of this controller IC ISL6223 include programmable VID codes from the microprocessor that range from 0.925V to 2.00V with a system accuracy of ±1%.Pull up currents on these VID pins eliminates the need for external pull up resistors. In addition "droop" compensation,used to reduce the overshoot or undershoot of the CORE voltage, is easily programmed with a single resistor.

Another feature of this controller IC ISL6223 is the PGOOD monitor circuit which is held low until the CORE voltage increases,during its Soft-Start sequence, to 0.9V. Overvoltage, the CORE voltage going above 2.35V, results in the converter shutting down and turning the lower MOSFETs ON to clamp and protect the microprocessor. Under voltage is also detected and results in PGOOD low if the CORE voltage falls below 0.9V. Overcurrent protection reduces the regulator current to less than 25% of the programmed trip value. An external capacitor connected to the DACOUT pin and ground slows down the transition of the DAC output to avoid triggering the overcurrent protection when the VID code changes. These features provide monitoring and protection for the microprocessor and power system.