First Digital Multiphase PWM Controllers with AVSBus and Synthetic Current Control

MILPITAS, CA -- Intersil Corporation introduces 12 new digital multiphase controllers and a companion smart power stage, including the industry's first digital solution with an Adaptive Voltage Scaling Bus (AVSBus™). The new digital controllers provide up to seven phases assignable in any combination across two outputs, and combine with smart power stages to provide a scalable solution from 10A to 450A. The result is enhanced power optimization and more energy-efficient networking and communications infrastructure equipment.

AVSBus joins the PMBus™ v1.3 specification and features a 50MHz high-speed bus that connects directly to the processor to communicate telemetry data and deliver efficiency savings through adaptive voltage positioning. Intersil's new DC/DC controllers and ISL99227 60A smart power stage support demanding CPU core voltages, memory, and auxiliary power rails, enabling power designers to customize their solution to meet any rail requirements. Watch a video on this digital multiphase power solution.

The digital multiphase family is comprised of three groups of controllers. The ISL68137 and ISL68134 controllers utilize the AVSBus to power and communicate with ARM-based processors in network routers, switches, servers, storage, and wireless telecom equipment. Two general-purpose controllers (ISL68127 and ISL68124) power network processors, FPGAs, SoCs and graphics accelerators. And eight controllers (ISL69147/44, ISL69137/34, ISL69128/27 and ISL69125/24) add a secondary high-speed interface (SVID or SVI2) to power the latest Intel and AMD processors in cloud computing applications that make up the Internet of Things (IoT) backbone.

The ISL681xx and ISL691xx controllers integrate a high performance digital engine featuring a patented synthetic current control architecture that tracks each phase current with zero latency. This allows the device to respond to any load transient with precise current and voltage positioning, and 30% less capacitance than competitive devices. Synthetic current control also makes it possible to develop high reliability systems using all ceramic capacitors.

Engineers are able to realize the flexibility and benefit of digital control through Intersil's easy to use PowerNavigator™ GUI software tool. PowerNavigator connects to development boards communicating across PMBus and AVSBus, allowing engineers to set up and control all parameters, optimize efficiency via precise current thresholds for adding/dropping phases, and adjust the loop tuning. PowerNavigator eliminates board rework as designs are completed with on the fly changes for stability tuning and optimization. The final configuration is simply stored to non-volatile memory.

Key Features and Specifications of ISL681xx and ISL691xx Controllers
•PMBus 1.3 and AVSBus compliant ◦Telemetry for Vin, Vout, input/output current, and temperature diagnostic fault reporting with black box capability
◦ISL68137 and ISL68134 include AVSBus interface for adaptive voltage scaling

•Proprietary digital control scheme with patented synthetic current control ◦Full bandwidth, zero latency current waveforms digitized per phase
◦Fast transient response supporting minimal output capacitance, including all MLCC

•Flexible phase configuration ◦Configurable PWMs, ability to assign phases to any output (X+Y)
◦Allows solution to be scaled in current from 10A to 450A

•Power Stage Support ◦Supports ISL99227 60A smart power stage with integrated current sensing
◦Supports ISL6617A phase doubler for extending to 14 phase operation

•Intuitive setup, control and monitoring via PowerNavigator GUI ◦Cycle by cycle current protection with average and peak thresholds
◦Autonomous auto phase dropping (APD) with adjustable current thresholds
◦Output and input over-voltage and under-voltage protection

Key Features and Specifications of ISL99227 60A Smart Power Stage
•Input voltage range of 4.5V to 18V
•60A current capability with 25V rated synchronous FETs
•Integrated current sensing, 3% accuracy across line, load and temperature
•Differential current reporting at 5mV/A eliminating DCR error and noise
•3.3V compatible tri-state PWM input
•Integrated temperature sensing with fault monitoring
•High side FET over-current protection

Pricing and Availability

The ISL681xx and ISL691xx digital multiphase controllers and ISL99227 smart power stage are available now, with detailed controller pricing in the table below. The ISL99227 smart power stage is supplied in a 5mm x 5mm, 32-lead QFN package and is priced at $5.21 USD in 1k quantities. Development boards are also available to help engineers scale power supply performance and select connectivity requirements for rapid prototyping and development.

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