Digital multi-phase PWM controllers make IoT ‘greener’
Three families made up of 12 digital, multi-phase controllers and a smart power stage are announced by Intersil. The digital controllers provide up to seven phases, assignable across two outputs, and combine with smart power stages to provide a scalable solution from 10 to 450A. It says that the result is enhanced power optimisation and more energy-efficient networking and communications infrastructure equipment.
The digital multiphase family is comprised of three groups of controllers. The ISL68137 and ISL68134 controllers use the Adaptive Voltage Scaling Bus (AVSBus) to power and communicate with ARM-based processors in network routers, switches, servers, storage, and wireless telecomms equipment.
Two general-purpose controllers (ISL68127 and ISL68124) power network processors, FPGAs, SoCs and graphics accelerators. 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.
The ISL681xx and ISL691xx controllers integrate a high performance digital engine, featuring a patented synthetic current control architecture. The architecture tracks each phase current with zero latency, allowing the device to respond to any load transient with precise current and voltage positioning, and 30 per cent less capacitance than competitive devices, says the company. Synthetic current control also makes it possible to develop reliable systems using all ceramic capacitors.
The PowerNavigator GUI tool connects to development boards communicating across PMBus and AVSBus, allowing engineers to set up and control all parameters, optimise efficiency via precise current thresholds for adding/dropping phases, and adjust the loop tuning. It eliminates board rework as designs are completed with on-the-fly changes for stability tuning and optimisation. The final configuration is stored to non-volatile memory.
The ISL681xx and ISL691xx controllers are PMBus 1.3 and AVSBus-compliant and have telemetry for Vin, Vout, I/O current, and temperature diagnostic fault reporting with black box capability.
There is support for ISL99227 60A smart power stage with integrated current sensing and for the ISL6617A phase doubler for extending to 14-phase operation.
Features of the ISL99227 60A smart power stage include an input voltage range of 4.5 to 18V, 60A current capability with 25V rated synchronous FETs, integrated current sensing, three per cent accuracy across line, load and temperature and differential current reporting at 5mV/A, eliminating DCR error and noise.
The ISL681xx and ISL691xx digital multiphase controllers and ISL99227 smart power stage are available now. The ISL99227 smart power stage is supplied in a 5.0 x 5.0mm, 32-lead QFN. Development boards are also available.