The ISL6334, ISL6334A control microprocessor core voltage
regulation by driving up to 4 interleaved synchronous-rectified
buck channels in parallel. This multiphase architecture results
in multiplying channel ripple frequency and reducing input and
output ripple currents. Lower ripple results in fewer
components, lower cost, reduced power dissipation, and
smaller implementation area.
Microprocessor loads can generate load transients with
extremely fast edge rates and requires high efficiency at light
load. The ISL6334, ISL6334A utilizes Intersil’s proprietary
Active Pulse Positioning (APP), Adaptive Phase Alignment
(APA) modulation scheme, active phase adding and
dropping to achieve and maintain the extremely fast
transient response with fewer output capacitors and high
efficiency from light to full load.
The ISL6334, ISL6334A is designed to be completely
compliant with Intel VR11.1 specifications. It accurately
reports the load current via IMON pin to the microprocessor,
which sends an active low PSI# signal to the controller at low
power mode. The controller then enters 1- or 2-phase
operation with diode emulation option to reduce magnetic
core and switching losses, yielding high efficiency at light
load. After the PSI# signal is de-asserted, the dropped
phase(s) are added back to sustain heavy load transient response and efficiency.