Robert i am a designer but i need to go depth of practical design. will you course let me direct in this path? do differential pair need to be in length match too with other ddr3 data and address signals? or just with each other.
Nice video! Do you know if the auto router or interactive router will follow design rules for length matching? When routing multiple connections interactively, it seems the length matching rules are ignored, only to need manual fixing afterward. The Situs router appears to ignore length matching rules, and the exporter for Specctra also seems to ignore length matching rules. Manually setting up rules in Specctra works and Specctra does a wonderful job, but Situs appears unable to do length matching. Thank you. Your videos are very informative. :)
Kevin Rouviere Thank you Kevin. About your question - I do not use autorouter and I normally only route one connection, so I really don't know. Maybe someone else can help?
sir, how to import pads layout pcb file in pads without schematic, itried to import but the copper pour and net is not connected well and some unconnected nets are also ther, please make a videos on these issues also, thanks
Hello Mr Feranec! I need to connect a microcontroller, a sdram and a flash memory and some data lines are common. How should i split the routes to have same length from the microcontroller to the sdram memory and from the sdram to the flash? Thank you!
if my VBUS is thin and i mean very thin but it must care out 20V up to 3A or even 5A does the huge ground help ? to not burn out the PCK track ? i mean if the GND is plane. for USB C i know this is not the right place to ask question but fell like someone who already know can asnwer.
Hello Chrystian, routed length is sum of the track segments, the signal length can add stuff like length in the via, length in footprint and it also calculate it more precisely (e.g. it finds and measures the shortest distance between two pins). Have a look here, that may help: ua-cam.com/video/jpk-hfsFaqA/v-deo.html
Robert Feranec I meant the length of the trace say example You look at DDR memory where do you get the optimum length match in the datasheet? also if it isnt supplied say Im working on an old sharc dsp 21065L dsp it uses some flash and SRAM non of the components supply trace length info where do I get it from ?
***** Usually, all requirements are specified in Design guide. For example, for this particular case, you can find more info here: www.fedevel.com/welldoneblog/2014/06/ddr3-length-matching-rules/
Robert Feranec i work with pcb single sided, and I need to route high speed usb2. impedance is kept constant 90 ohms on my pcb, means a differential pair separation 7.5 mils and 50 mils track! It is difficult to maintain constant impedance, then I want to keep as close as possible the length of the differential pair. I often find much difference between the length of N and P and not how to adjust without breaking the parallelism. Thanks!
hi robb.. thanks for sharing you knowledge which is price less, im very thankful to you. i have a doubt about this length matching, here in this video you didn't explained how to set length for nets. i understand what is the purpose of length matching through your explanation but how to select a particular net, is what im not getting please can you explain me .
It depends on what you are routing - check out your chip design guide. Generally nets in one group should be routed similar length (shortest and longest length must fit into a tolerance e.g. maximum difference between shortest and longest track must not be bigger than XX mils ). Then, there are relative length rules - not supported by Altium. These are for example rules like ADDR/CMD/CTL group can not be longer than CLK group and can not be shorter than CLK-XXXmil
okay but im asking is different, for example i want to perform length tunning for net1 net2 net 3...net10 tracks. how to set length for selected nets? that is my question. waiting for your answer
i m sorry for not being clear, for example i am routing an IC which has 20 pins and all are connected to Micro-controller.Now i want to rout them by using length tunning. Here i have to select the length of each track as same(eg-30mm), because that is the purpose of length tunning na.how to achive that 30mm for all the track nets. that is my question hope im clear this time.... And one more i want to ask you,before i m working with protel now just started with altium. i m facing a problem in one issue i.e., i will have designators and component values when i update pcb. In protel if i click one of the designator i can edit its size and can hide it and it can be applied to all other designators by using global option in protel.. But here in altium i am able to change only one at a time.For each component i have to change it again which is very difficult and time consuming as i have many components(700) in my PCB. Please tell me the option to make it global to all components. waiting for your answer querulously.
Where do I use this strategy? I mean does it good in critical designing Only or Else I can follow it in regular microcontroller based Design. And what is the benefits of line matching strategy?
Simple answer is - mostly DDR2/3/4/X memories and differential pairs. But you may need to consider it also in some slower interfaces - e.g. you may want to have data bus similar length or clock signal the longest - however the length matching criteria are not so strict for slower interfaces (e.g. difference can be 25.4mm / 1000mils or more), so it is not so visible there. Simply to say, the goal is, that the signals will arrive in controlled order e.g. all data signals will arrive together and little bit later the clock will arrive.
Hi Robert! I followed your instructions but somehow the wave turns out squared not mitered like yours (and being a good student I know that using squared waves is bad practice). Changing the style from the properties doesn't affect the result :/
Great video as always! I have Altium 20.1.14 and I have a differential pair that have the diff pair class name of USB3. I have a rule (set to highest priority) that I have set to a 5 mil max difference in the length within the diff pair (and the rule is set to diff pair class name USB3 and I press the "test queries" button to make sure it is applying to the correct diff pair). Yet I can go to the PCB panel and see the 2 nets in the USB3 diff pair are more than 5 mil difference in length. Yet I get no error (no error on the board and no length number highlighted in yellow). I have the online rule checker enabled, the rule is enabled, and I have that rule set to "online" and "batch". Any ideas why it doesn't generate an error? I have the same behavior for the diff pair impedance rule. If I manually make the gap between the traces too much, it does not cause an error. Thank you!
Can someone tell me how to lock the "tuned trace"? Because when I click the tab button to select the whole trace the lock option vanished from the side bar.
Double check what everything is selected - maybe your selection includes objects which can not be locked and that is why you are not getting the lock option? Possibly use mask + filter for tracks and vias only and try to select it this way.
@@aqibwahidbutt5316 Maybe you need to do right click on a track and then Unions -> Explode Length Tuning to Free Primitives. That will change the length tuned part to standard tracks.
Great video robert,
You can not imagine that in my proj i did lengh matching first time ever after watching this video.
Your the man Robert, your videos are rock solid!
+Kris Kizlyk Thank you. I am happy you like them :)
Great tutorial Robert
Absolutely perfect. I wasn't clicking the magic button :) but now I'm all set, thanks to you. I am off checking out your other videos!! G'day mate!
Thank you Isti :)
thanks for your all share,,,
Excellent reference for today
Thank you Greg
You are a life saver Robert! Honestly!
Glad to help Liza
Thanks a lot Robert. So useful.
As always: very helpful. Thanks.
you are fantastic buddy...this is so usefull series....tons of thanks buddy
Thank you nil :)
thanks for video Robert, it is very helpful.
Thank you Mehmet
Awesome Videos thanks
Robert i am a designer but i need to go depth of practical design. will you course let me direct in this path?
do differential pair need to be in length match too with other ddr3 data and address signals?
or just with each other.
Thank you so much budy this is really really useful!
Your videos are genial. Thanks a lot for this work
Thank you Gabriel
Very nice. Thanks.
In this routing amplitude and gap what value to fix. For ex. 3*W amplitude and 2*S use this
Great vid, thank you.
+Łukasz Przeniosło Glad to help. Thank you for leaving your feedback :)
Cool info, thanks :)
Hi ,Sir. To do the same length of the data and Addres arrays, What could l do as the easiest or optimum solution? Briefly give your recommendation
Thanks Robert ..
Great video!
Thank you
Nice video! Do you know if the auto router or interactive router will follow design rules for length matching? When routing multiple connections interactively, it seems the length matching rules are ignored, only to need manual fixing afterward. The Situs router appears to ignore length matching rules, and the exporter for Specctra also seems to ignore length matching rules. Manually setting up rules in Specctra works and Specctra does a wonderful job, but Situs appears unable to do length matching.
Thank you. Your videos are very informative. :)
Kevin Rouviere Thank you Kevin. About your question - I do not use autorouter and I normally only route one connection, so I really don't know. Maybe someone else can help?
sir, how to import pads layout pcb file in pads without schematic, itried to import but the copper pour and net is not connected well and some unconnected nets are also ther, please make a videos on these issues also, thanks
How do you determine the path length to be 33mm?
Hello Mr Feranec! I need to connect a microcontroller, a sdram and a flash memory and some data lines are common. How should i split the routes to have same length from the microcontroller to the sdram memory and from the sdram to the flash? Thank you!
Hello Marius. Please, post your question on our forum here: www.fedevel.com/designhelp/
if my VBUS is thin and i mean very thin but it must care out 20V up to 3A or even 5A does the huge ground help ? to not burn out the PCK track ? i mean if the GND is plane. for USB C
i know this is not the right place to ask question but fell like someone who already know can asnwer.
both connections need to be wide .. GND and also power
Hi sir, Can you make a full flex pcb tutorial from schematic to Gerber in altium?
KING !
Hello Robert !
What is the difference between the signal length and the routed length ?
Hello Chrystian, routed length is sum of the track segments, the signal length can add stuff like length in the via, length in footprint and it also calculate it more precisely (e.g. it finds and measures the shortest distance between two pins). Have a look here, that may help: ua-cam.com/video/jpk-hfsFaqA/v-deo.html
Nice one Robert. Question where does one get the information for the the length if length is not given ?
Thank you. What do you mean by "is not given"?
Robert Feranec I meant the length of the trace say example You look at DDR memory where do you get the optimum length match in the datasheet? also if it isnt supplied say Im working on an old sharc dsp 21065L dsp it uses some flash and SRAM non of the components supply trace length info where do I get it from ?
***** Usually, all requirements are specified in Design guide. For example, for this particular case, you can find more info here: www.fedevel.com/welldoneblog/2014/06/ddr3-length-matching-rules/
how to calculate trace width for hight voltage PCB ?
Please,you could do a video of how to tune lengths on differential pairs? Thanks!
Do you mean within a pair of between pairs?
Robert Feranec i work with pcb single sided, and I need to route high speed usb2. impedance is kept constant 90 ohms on my pcb, means a differential pair separation 7.5 mils and 50 mils track! It is difficult to maintain constant impedance, then I want to keep as close as possible the length of the differential pair. I often find much difference between the length of N and P and not how to adjust without breaking the parallelism. Thanks!
Where I will get thiz software for practice
hi robb.. thanks for sharing you knowledge which is price less, im very thankful to you.
i have a doubt about this length matching, here in this video you didn't explained how to set length for nets. i understand what is the purpose of length matching through your explanation but how to select a particular net, is what im not getting please can you explain me .
It depends on what you are routing - check out your chip design guide. Generally nets in one group should be routed similar length (shortest and longest length must fit into a tolerance e.g. maximum difference between shortest and longest track must not be bigger than XX mils ). Then, there are relative length rules - not supported by Altium. These are for example rules like ADDR/CMD/CTL group can not be longer than CLK group and can not be shorter than CLK-XXXmil
okay but im asking is different, for example i want to perform length tunning for net1 net2 net 3...net10 tracks. how to set length for selected nets? that is my question. waiting for your answer
Set length in Altium? I am not really sure what you mean when you say "set length".
i m sorry for not being clear, for example i am routing an IC which has 20 pins and all are connected to Micro-controller.Now i want to rout them by using length tunning. Here i have to select the length of each track as same(eg-30mm), because that is the purpose of length tunning na.how to achive that 30mm for all the track nets. that is my question hope im clear this time....
And one more i want to ask you,before i m working with protel now just started with altium. i m facing a problem in one issue i.e., i will have designators and component values when i update pcb.
In protel if i click one of the designator i can edit its size and can hide it and it can be applied to all other designators by using global option in protel.. But here in altium i am able to change only one at a time.For each component i have to change it again which is very difficult and time consuming as i have many components(700) in my PCB. Please tell me the option to make it global to all components.
waiting for your answer querulously.
Where do I use this strategy?
I mean does it good in critical designing Only or Else I can follow it in regular microcontroller based Design.
And what is the benefits of line matching strategy?
Simple answer is - mostly DDR2/3/4/X memories and differential pairs. But you may need to consider it also in some slower interfaces - e.g. you may want to have data bus similar length or clock signal the longest - however the length matching criteria are not so strict for slower interfaces (e.g. difference can be 25.4mm / 1000mils or more), so it is not so visible there. Simply to say, the goal is, that the signals will arrive in controlled order e.g. all data signals will arrive together and little bit later the clock will arrive.
traces are locked in altium. how to remove the lock primitives.
and how to select the only ttraces, or only vias in altium,
Hi Robert! I followed your instructions but somehow the wave turns out squared not mitered like yours (and being a good student I know that using squared waves is bad practice). Changing the style from the properties doesn't affect the result :/
+Urmo Kõiv Oh well.. I found the solution to increase the miter radius by pressing '2' :) And thanks for sharing your knowledge!
+Urmo Kõiv :)
Great video as always! I have Altium 20.1.14 and I have a differential pair that have the diff pair class name of USB3. I have a rule (set to highest priority) that I have set to a 5 mil max difference in the length within the diff pair (and the rule is set to diff pair class name USB3 and I press the "test queries" button to make sure it is applying to the correct diff pair). Yet I can go to the PCB panel and see the 2 nets in the USB3 diff pair are more than 5 mil difference in length. Yet I get no error (no error on the board and no length number highlighted in yellow). I have the online rule checker enabled, the rule is enabled, and I have that rule set to "online" and "batch". Any ideas why it doesn't generate an error? I have the same behavior for the diff pair impedance rule. If I manually make the gap between the traces too much, it does not cause an error. Thank you!
Thank you Shane. PS: Check your setting in Max Uncoupled Length inside Differential Pairs Routing rule
Can someone tell me how to lock the "tuned trace"? Because when I click the tab button to select the whole trace the lock option vanished from the side bar.
Double check what everything is selected - maybe your selection includes objects which can not be locked and that is why you are not getting the lock option? Possibly use mask + filter for tracks and vias only and try to select it this way.
Found the lock symbol using filter option.
Thanks
But why it didn't appear when I select the length tuned portion?any guess?
@@aqibwahidbutt5316 Maybe you need to do right click on a track and then Unions -> Explode Length Tuning to Free Primitives. That will change the length tuned part to standard tracks.
Worked! 👍
Thanks 😊
Sometimes the tracks do not move at all,why?
Altium is not very good in automatic length matching
Moving the mouse while length matching doesn't help :(
Using AD19