Analog Design Journal

Addressing the protection challenges of 48V AI servers using hot-swap controllers

Authored by Avishek Pal and Rakesh Panguloori

With advancements in artificial intelligence and machine learning, enterprise servers have become extremely power-hungry as they simultaneously process a large amount of data and storage. The steady state power rating of each server motherboard has gone up, but the form factor remains the same, which imposes system design challenges. In this article, we’ll discuss various challenges that AI-based processors bring into 48V server designs, along with design guidelines and important tips and tricks for the design and layout to achieve a reliable hot-swap solution for the system specifications.

Transient protection design for power switches to achieve reliable power-path protection

Authored by Rakesh Panguloori and Kunal Goel

Component integration in modern electronic systems enhances performance by increasing functionality. Most of these systems that use sensitive and expensive electronic devices need protection. Traditional protection solutions are inaccurate, slower to respond and lack configurability and repeatability. Thus, active circuit protection using eFuse and hot-swap solutions have begun to replace discrete front-end protection circuits in many applications. In this article, we’ll discuss electrical overstress and the design process for transient protection components in a 200A eFuse enterprise server application, including placement and PCB layout considerations.

Sampling around Nyquist holes in high-speed converters

Authored by Chase Wood, Rob Reeder and Luke Allen 

Frequency planning is a paramount part of any frequency-based application. Making sure the frequencies of interest are valid, within band, and not reduced to the degree where spurious dynamic range is lost should be part of any frequency development strategy. In this paper, we will cover high-speed ADC Nyquist rules as they apply to super Nyquist sampling. We will also cover how to use decimation to aide in your frequency plan and how to guard band against falling into a frequency “hole” during the design and development stage.

How to limit PFC re-rush current

Authored by Bosheng Sun

The recently released Modular Hardware System – Common Redundant Power Supply (M-CRPS) specification requires the re-rush current (which is different from the well-known inrush current) needs to be limited when the input voltage resumes after an input brownout or blackout event on the power supply used in data center. Previously, this re-rush current was unspecified, and no special control action for this event existed. This article presents a low-cost, simple and very effective method to meet the M-CRPS requirement.

Optimizing signal chain cost and accuracy for isolated current sensing in energy metering

Authored by Dr. Ralph Oberhuber

As we move toward a more sustainable energy grid with sources such as solar and wind power, the need arises for energy metering devices to obtain detailed insights into individual power consumption in order to identify areas for improvement, optimize usage, and reduce costs. For each of the signal-chain components used in these types of systems, performance, size and cost trade-offs exist. This article focuses on the performance vs. cost trade-offs for the current measurement sensor and signal conditioning, as well as the ADC.