High-integration DC/DC digital PWM power controller

September 30, 2014 // By Graham Prophet
Designed for power regulation in densely-populated infrastructure power systems, the ZL8801 allows for high current digital supplies to be configured as dual phase or in parallel to supply over 300A of load current to high-end FPGAs and ASICs.

The ZL8801 dual-phase, DC/DC digital PWM controller enables a simple dual phase solution for higher current applications ranging from 40A to 100A. With the ability to current share across multiple devices, its range can be extended up to 300A for high-end FPGAs and ASICs employed in densely populated power supplies in servers, storage equipment and basestations. Used in conjunction with Intersil's PowerNavigator graphical user interface (GUI), the ZL8801 simplifies the system power conversion design process.

The ZL8801 uses Intersil's digital power technology ChargeMode control loop architecture to deliver transient response performance superior to analogue controllers. Inherently stable, the ZL8801's fully digital control loop corrects errors cycle-by-cycle, eliminating the need for compensation. Its high control loop bandwidth reduces the amount of output capacitance needed to meet the latest transient requirements of high-end FPGAs and ASICs, resulting in a smaller board size and lower bill of materials cost. The ZL8801 can be paired with the ISL99140 40A DrMOS (Integrated Driver and MOSFET) output stage to create a complete voltage regulator solution.

The ZL8801 supports Intersils DDC (digital DC) bus for inter-controller communication. This bus allows for system-based sequencing, fault management and current sharing in conjunction with other Intersil digital power ICs, all on a single wire. Configuration is managed with the graphical PowerNavigator tool to provide drag and drop sequencing control, which is autonomously managed in-system by the ZL8801. Current sharing is enabled by the DDC bus, allowing up to four ZL8801s to be paralleled providing for high current power system designs.

Modern systems have increased complexity and reliability demands requiring designers to control and monitor every power rail to maximise efficiency and reduce downtime. This has historically been achieved through the use of numerous discrete monitors, sequencers and system controllers to provide added functionality around the PoL converters. The ZL8801 integrates all of these functions, so a designer can monitor and control every aspect of the power supply through a PMBus