Stitching Together A Multi-Layer PCB PDN


A printed circuit board (PCB) is much like a complicated city, with a myriad of intertwined pathways for data signals and power. To meet the electric current needs of modern, high-powered integrated circuits (ICs), the power distribution network (PDN) usually consists of wide power planes on multiple layers to provide a low-resistance path for power delivery. These planes are stitched together ... » read more

Top500: Frontier Is Still On Top


The latest versions of the Top500 and Green500 lists were just released on May 22, 2023. The last time that I wrote about the Green500, a Chinese machine, NRCPC’s Sunway TaihuLight, was sitting at the top of the Top500 list. It’s been a while since I last wrote about these lists and it’s interesting to look back at the leap in performance and energy efficiency over the past 7 years. ... » read more

The History Of CMOS


Since CMOS has been around for about 50 years, a comprehensive history would be a book. This blog focuses on what I consider the major transitions. NMOS Before CMOS, there was NMOS (also PMOS, but I have no direct experience with that). An NMOS gate consisted of a network of N-transistors between the output and Vss, and a resistor (actually a transistor with an implant) between the output and... » read more

An Ideal Always-Sensing Subsystem Architecture


Always-sensing cameras are a relatively new method for users to interact with their smartphones, home appliances, and other consumer devices. Like always-listening audio-based Siri and Alexa, always-sensing cameras enable a seamless, more natural user experience. Through continuous sampling and analyzing visual data, always-sensing enables use cases such as: “Find a face” detection for... » read more

Connectivity Challenges In Industry 4.0


Industry 4.0 is characterized by interoperability (such as IIoT), information transparency (digital plant models: virtual copy of physical world), technical support (the ability of cyber-physical systems to support humans by executing various tasks), and decentralized decision-making. IIoT allows devices to be connected, creating a virtual copy of real-world data that allows operators to visual... » read more

No One-Size-Fits-All Approach To RISC-V Processor Optimization


As the demand for high-performance processors continues to grow and semiconductor scaling laws continue to show their limits, the need for processor optimization is inevitable. As I explained in a previous blog, RISC-V is designed to enable this. However, there is no one-size-fits-all approach to processor optimization. As each workload and each application will have their own requirements, th... » read more

Distribution Of Currents In Via Arrays


It has become increasingly difficult in recent years to provide adequate PDNs on a PCB. The sheer number of different voltages, combined with increased current demands, makes distributing current around the board a substantial layout challenge. This paper demonstrates that by using appropriate and accurate simulations, combined with the improved intuition that such simulations bring, it is a ch... » read more

Architectural Considerations For Compute-In-Memory In AI Inference


Can Compute-in-Memory (CIM) bring new benefits to AI (Artificial Intelligence) inference? CIM is not an AI solution; rather, it is a memory management solution. CIM could bring advantages to AI processing by speeding up the multiplication operation at the heart of AI model execution. To read more, click here. » read more

A Formal-Based Approach For Efficient RISC-V Processor Verification


The openness of RISC-V allows customizing and extending the architecture and microarchitecture of a RISC-V based core to meet specific requirements. This appetite for more design freedom is also shifting the verification responsibility to a growing community of developers. Processor verification, however, is never easy. The very novelty and flexibility of the new specification results in new fu... » read more

Blog Review: May 24


Siemens' Patrick McGoff finds that designers have not had easy tools to address solderability, leaving a critical part of the manufacturing success of a PCB to the component engineer or the contract manufacturer, and points to manufacturing-driven design as a way to avoid quality issues later. Cadence's Rich Chang finds that effective UPF low-power verification and debug involves more than o... » read more

← Older posts Newer posts →