In this article, I am going to talk about the definitions of setup time and hold time, as well as the calculation of circuit’s performance limits where setup time and hold time should be considered.For digital sequential logic design, clock timing is the most critical problem to ensure functional corectness. Basically, the delay path between […]
How To Fast Build Testbench For Module Test
Does an IC designer need to know about verification skills? Personally, I suggest that it is necessary to understand the basic methodologies. To have an in-depth understanding of either VMM/UVM methodology may take three or five months, but to just learn the core idea of how and why to build it can cost you maybe […]
Stop Creating Clocks & Resets Locally
When this topic first came to my mind, I was hanging out on a beach in Tsingtao. It has been so long since the last time when I went to a beach. The warm and overwhelming salty smell of Tsingtao beach reminded me of the old time when I was cycling along the Southampton Water […]
One-hot State Machine
When I was checking the source code of ARM7-TDMI, a very unusual state machine caught my attention. It was used in the codes of the ALU’s multipliers. After doing some researches, I finally figured out that it was the so-called ‘One-hot State Machine’. I have heard about this kind of state machine when I was […]
Computer System Architecture Study Note
作者：Kellen Wang 1. 架构与功耗 在电压给定、工作量给定的情况下，降低计算机频率或许可以降低芯片的表面温度，但完成工作量所花费的实际功耗并不会因此降低。如果真的想降低系统功耗的话，必须在降低工作频率的同时降低系统电压。由于功耗与电压是平方关系，只要电压下降一半，功耗就会下降为之前的四分之一，再乘上频率的同比例降低，整个系统的实际功耗会下降为之前的八分之一。因此20年来系统内核电压一直在不断下降，从5V一直降到现在的1V。 随着制程的不断上升，芯片面积越来越小，散热问题越来越严峻。在解决散热问题之前，时钟频率似乎已经到达了一个瓶颈。因此，从2003年以后系统主频就鲜有上升，一直维持在最高3.3Ghz左右。 +30
What is Good Verilog Coding Style
Recently, I was asked by my boss to make some rules to regulate the verilog coding style in my team. For confidentiality reasons, I wouldn\’t be able to share the whole pages with you, but still I would like to point out some little tips that I personally strongly recommend you to adopt. I. Example […]
The Knowledge Base Of A Qualified IC Design Engineer
When I just graduated from school, I deemed myself as an already qualified digital IC design engineer. However, I soon learnt how stupid I was once I started my career as an engineer. I have seen many great engineers in companies, and I have learnt a lot from them. In this article, I would love […]