This reference design shares an overview about the Analog Devices' proprietary solution for the OCP ORV3 Battery Back-up Unit reference design, leveraging the company's array of resources, including power converters, controllers, power and battery management products, microcontrollers, high-performance supervisors, and more. The webpage will offer a brief summary and explanation of a battery backup unit, outlining its application in data center scenarios.
The Open Compute Project, abbreviated as OCP, is an organization that facilitates the sharing of designs and best practices for data center products among various companies, including Meta, IBM, Intel, Google, Microsoft, HP, Nokia, and more. OCP originated internally at Facebook HQ as “Project Freedom” in 2009.
Designed for deployment on a BBU Shelf within a data center rack, a Battery Back-up Unit (BBU) serves the purpose of supplying DC power to system loads in the event of sudden power interruptions. OCP has established a set of design requirements and specifications for the BBU reference design standard.
As an illustration, a key requirement for an individual BBU module is its ability to deliver a backup power of 3kW for a duration of 4 minutes and a charging power of 250W over a period ranging from three to six hours.
To see additional details regarding the established BBU standard specifications, please refer to the following link:
The block diagram comprises of the main power converter, LT8228, functioning as a bidirectional controller for the BBU's charging and discharging processes. Additionally, to augment the backup power available during battery discharging, the power converter design incorporates the multiphase expander, LT8551. The combined operation of LT8228 and LT8551 enhances the backup discharging power to 3kW and the charging power to 250W.
To serve as the battery management system device for the BBU, ADBMS6948 has been introduced. Paired with its dedicated microcontroller, MAX32625, it has the capability to provide comprehensive routine maintenance and monitoring of the BBU's battery stack.
With regards to power system and fault monitoring, the power management IC, LTC2971, was employed in conjunction with MAX32690, acting as the primary microcontroller and brain of the BBU. MAX32690 is responsible for logic control, communications, housekeeping, and fault handling within the BBU.
A graphical user interface has been created to offer a visual logical sequence of operations for the device, ensuring a meticulously planned execution of housekeeping and protection tasks. The GUI also plays a pivotal role in facilitating well-organized and object-oriented monitoring, reading, and providing easy access for customers.
The graphical user interface (GUI) for the BBU module is divided into various sections, each offering crucial information to the user. The following details the functions of each section:
The GUI only allows the display of one module at a time, and users have the flexibility to select which specific module's data they want to view on the interface.
A comprehensive five-part technical article series about the BBU reference design will be published on Analog Dialogue, commencing in December 2023. Stay tuned for the release of the articles, and links to each installment will be provided.
Feel free to watch this Webinar which talks about the complete design journey for the company's BBU Reference design which meets the OCP ORV3 specification for data centers.