30A high integration DC/DC for FPGA point-of-load regulation

March 12, 2015 // By Graham Prophet
A DC/DC conversion module from Altera’s Enpirion acquisition features adaptive digital control and is optimised to power FPGA cores: specifically, Altera’s Generation 10 devices of which the Arria 10 variants are now shipping.

The 30A PowerSoC DC-DC step-down converter is presented as the first in a family of integrated digital DC-DC step-down converters that will provide power management for Altera’s Generation 10 FPGAs, such as the core and transceiver power supply rails of Arria 10 and Stratix 10 FPGAs.

Altera claims the EM1130 as having the densest-available footprint, with close output regulation, and fast transient response. The digitally-controlled modules are equipped with PMBus which provides the interface for Altera SmartVID technology which allows the converter to provide the Arria 10 and Stratix 10 FPGAs with a lower voltage (Vcc) for significant power savings while maintaining the performance of the specific device speed grade. (Each device in the family is delivered at a specified speed grade, and within the grading, each individual part is characterised for peak performance at a precise voltage. Optimum voltages are programmed into the FPGA, and it is this rail value that the programmable part can demand from the regulator.) PMBus also allows the EM1130 to communicate with the system to provide telemetry—measurement of key parameters such as current, voltage and temperature.

Altera says that the EM1130 is 50% smaller than other modules in its grade, with a 2-4% efficiency point improvement enabling users to increase their system performance; it has a 30 to 50% improvement in telemetry accuracy (current and voltage measurement) allowing designers to extend the performance range of their systems. Adaptive control technology reduces external compensation components and adjusts automatically to provide a stable solution regardless of changing operating conditions. You can set it up via a graphical user interface (GUI) that simplifies programming.

Introducing the device, Altera’s Bob Blake highlighted the performance of the regulator in output quality, “At less than 10 mV ripple, we can look at [in some applications] replacing LDOs.” Acknowledging that the part has been optimised for the company’s own programmable devices, he adds that its performance means that applications will exist in other areas. This regulator will drop from a line of up to 14V, with a maximum of 3.3V output, providing an accuracy of 0.5% in response to the SmartVID commands. Again, optimised to supply the Stratix and Arria parts, its efficiency curve has been optimised for a 1V output. Delivering up to 30A per module, you can parallel up to six of them.