The ISL6617 utilizes Intersil’s proprietary Phase Doubler

scheme to modulate two-phase power trains with single

PWM input. It doubles the number of phases that

Intersil’s multi-phase controllers ISL63xx can support.

When the enable pin (EN_PH_SYNC) is pulled low, the

PWM input is pulled high. This simplifies the phase

shedding implementation for some Intersil controllers

(VR10, VR11, VR11.1, and VR12 family) that can disable

the respective and higher phase(s) by pulling the

respective PWM line high.

The ISL6617 is designed to minimize the number of

analog signals that interface between the controller and

drivers in high phase count scalable applications. The

common COMP signal, which is usually seen in

conventional cascaded configuration, is not required; this

improves noise immunity and simplifies the layout.

Furthermore, the ISL6617 provides low part count and

low cost advantage over the conventional cascaded

technique.

By cascading the ISL6617 with another ISL6617 or

ISL6611A, it can quadruple the number of phases that

Intersil’s multi-phase controllers ISL63xx can support.

The ISL6617 also features Tri-State input and outputs

that recognize a high-impedance state, working together

with Intersil multiphase PWM controllers and driver

stages to prevent negative transients on the controlled

output voltage when operation is suspended. This feature

eliminates the need for the schottky diode that may be

utilized in a power system to protect the load from

excessive negative output voltage damage.

Features

• Proprietary Phase Doubler scheme with Phase

Shedding Function (Patent Pending)

• Enhanced Light to Full Load Efficiency

• Double or Quadruple Phase Count

• Patented Current Balancing with DCR Current

Sensing and Adjustable Gain

• Current Monitoring Output (IOUT) to Simplify

System Interface and Layout

• Triple-Level Enable Input for Mode Selection

• Dual PWM Output Drives for Two Synchronous

Rectified Bridges with Single PWM Input

• Channel Synchronization and Two Interleaving Options

• Tri-State PWM Input and Outputs for Output Stage

Shutdown

• Phase Enable Input and PWM Forced High Output to

Interface with Intersil’s Controller for Phase Shedding

• Overvoltage Protection

• Dual Flat No-Lead (DFN) Package

- Near Chip-Scale Package Footprint; Improves PCB

Utilization, Thinner Profile

- Pb-Free (RoHS Compliant)

Applications

• High Current Low Voltage DC/DC Converters

• High Frequency and High Efficiency VRM and VRD

• High Phase Count and Phase Shedding Applications

• 5V PWM Input Integrated Power Stage or DrMOS