As Zuken technology partners, we are often asked about how best to set PCB constraints for double-data-rate (DDR) memory, and how to route to those constraints. This question arose recently when we were asked to create a common style of DDR3 design for training, and we tried mining the web for detailed information on PCB constraints. There had to be something out there, we thought.<\/p>\n
We were right; but unfortunately the detail had to be excavated from a vast and comprehensive pile of information about devices and controllers. It was hard to find a brief but clear description of what a PCB designer needs, and why, for a basic DDR3 circuit.<\/p>\n
Necessity being the mother of invention I worked with Kevan Keech, an expert PCB designer, \u00a0to create the most straightforward, realistic example we could think of \u2013 captured in three short movies.<\/p>\n
In the first movie I explain the circuit, routing topology and constraints.<\/p>\n
In the second movie, Kevan constrains the PCB design.<\/p>\n
In the final movie, Kevan routes the PCB design step-by-step and at the end we summarize the results.<\/p>\n
We use a single design example from start to finish \u2013 a controller connected to five 1-Gbitx8 SDRAM devices. Levelling is enabled so that the SDRAMs can be routed using fly-by topology, as defined in JEDEC standards\u00a0and elsewhere.<\/p>\n
We hope you enjoy the movies and find them useful.<\/p>\n
If you\u2019ve taken a look, why not leave a comment below!<\/p>\n
\t\t\t\tAs Zuken technology partners, we are often asked about how best to set PCB constraints for double-data-rate (DDR) memory, and how to route to those constraints. This question arose recently when we were asked to create a common style of DDR3 design for training, and we tried mining the web for detailed information on PCB constraints. There had to be something out there, we thought.\t\t<\/p>\n","protected":false},"author":31,"featured_media":11146,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"om_disable_all_campaigns":false,"footnotes":"","_links_to":"","_links_to_target":""},"categories":[228],"tags":[264,15018,265,14243,277],"class_list":["post-5439","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-pcb-design","tag-constraint-management","tag-electronic","tag-high-speed","tag-how-to","tag-routing"],"acf":[],"yoast_head":"\n