Compliant with Intel IMVP8?, the ISL95857 provides a

complete power solution for Intel microprocessors supporting

core, graphics and system agent rails. The controller provides

control and protection for three Voltage Regulator (VR)

outputs. VR A and VR C outputs support 1-phase operation

only, while VR B is configurable for 2- or 1-phase operation. The

address options programmable for these three outputs allow

for maximum flexibility in support of the IMVP8? CPU. All three

VRs share a common serial control bus to communicate with the

CPU and achieve lower cost and smaller board area compared

with a two-chip approach.

Based on Intersil’s Robust Ripple Regulator (R3?) technology,

the R3? modulator has many advantages compared to

traditional modulators. These include faster transient settling

time, variable switching frequency in response to load

transients and improved light-load efficiency due to diode

emulation mode with load-dependent low switching frequency.

The ISL95857 has several other key features. The controller

provides PWM outputs, which support Intel DrMOS power

stages (or similar) and discrete power stages using the Intersil

ISL95808 high voltage synchronous rectified buck MOSFET

driver. The controller complies with IMVP8? PS4 power

requirements and supports power stages and drivers which

are compatible. The ISL95857 supports the system input

power monitor (PSYS) option. The controller supports either

DCR current sensing with a single NTC thermistor for DCR

temperature compensation or more precision through resistor

current sensing if desired. All three outputs feature remote

voltage sense, programmable IMAX, adjustable switching

frequency, OC protection and a single VR_READY power-good

indicator.

Features

? Supports Intel serial data bus interface

? System input power monitor (PSYS) supported

? Three output controller

- VR A supports 1-phase VR design

- VR B configurable for 2-, 1-phase VR design

- VR C supports 1-phase VR design

? 0.5 system accuracy over temperature

? Low supply current in PS4 state

? Supports multiple current sensing methods

- Lossless inductor DCR current sensing

- Precision resistor current sensing

? Differential remote voltage sensing

? Programmable SVID address

? Programmable VBOOT voltage at start-up

? Resistor programmable address selection, IMAX, and

switching frequency

? Adaptive body diode conduction time reduction

Applications

? IMVP8 compliant notebooks, desktops, ultrabooks and

tablets