power and signal wires design between tow PCB borad

Started by adream307 in sci.electronics.design5 years ago 6 replies
PCB

Hi, I am freshman in electronics design. Recently, I was troubled by the power and signal design in PCB board. I hope someone can help me, thank...

Hi, I am freshman in electronics design. Recently, I was troubled by the power and signal design in PCB board. I hope someone can help me, thank you. I have two PCB board, PCB A and PCB B. There is information exchanging these two PCB ,but PCB A and PCB are powered by separated power(5V DC power). At first, I just connect the signal wires between PCB A and PCB B, then I find both PCB A and PCB ...


PCB Copper Thickness Versus Rth - is this graph correct?

Started by Klaus Kragelund in sci.electronics.design4 years ago 14 replies
PCB

Hi I have a PCB, 50mm x 50mm, and I need to optimize cooling of the PCB. A num= ber of dissipating components are spread out on the PCB to...

Hi I have a PCB, 50mm x 50mm, and I need to optimize cooling of the PCB. A num= ber of dissipating components are spread out on the PCB to produce an unifo= rm temperature across the PCB. Currently I am using 0.5 Oz PCB thickness, but it is possible to increase t= hat to 1 Oz. So I was looking for a graph of the thermal resistance on a certain area of= PCB versus the copper thickness...


Creating a Schematic from a PCB - What tools are available.

Started by Jim Flanagan in sci.electronics.design5 years ago 6 replies
PCB

I have a desire to take a populated PCB, take a digital photo of the top and bottom, then import the images into a PCB layout tool. What would...

I have a desire to take a populated PCB, take a digital photo of the top and bottom, then import the images into a PCB layout tool. What would be ideal would be to lay components on top of the imported PCB image on a different layer, manually route these components (following the tracks from the image), then do a 'Forward Annotate' to create the schematic. I cannot seem to find a PCB layo...


PCB high current bars

Started by Jamie Morken in sci.electronics.design9 years ago 6 replies
PCB

Hi, Are these bars that are soldered onto PCB's to increase the current handling of the PCB stock...

Hi, Are these bars that are soldered onto PCB's to increase the current handling of the PCB stock items? http://rocketresearch.nekrom.com/new/PCB%20high%20current%20bars/PCB%20high%20current%20bars.jpg cheers, Jamie


_Anyone using DesignSpark PCB

Started by dcas...@krl.org in sci.electronics.design4 years ago 3 replies
PCB

Found Design Spark PCB program while looking at comments about Sprint PCB. No cost for commercial or hobby use. Sounds nice, but is...

Found Design Spark PCB program while looking at comments about Sprint PCB. No cost for commercial or hobby use. Sounds nice, but is it really? Dan


Free/Open Source PCB autorouter in development; help wanted

Started by lynchaj in sci.electronics.design6 years ago 34 replies
PCB

Hi, There are a few free/open source PCB autorouters available however using them has been quite difficult due to a lack of...

Hi, There are a few free/open source PCB autorouters available however using them has been quite difficult due to a lack of interchange standards. There are at least three available such as MUCS-PCB, gEDA PCB (includes autorouter), and the Topological Autorouter (experimental also part of gEDA PCB). The QAutorouter provides a solution of building the Specctra DSN import and SES export ...


How do I set the pcb-lesstif's min-silk DRC parameter

Started by Johann Klammer in sci.electronics.design2 years ago 1 reply
PCB

I got loads of errors for the 0805 smd resistors coz the silk lines are too thin. What I've tried: in .pcb/settings min-silk = 1.00 mil in...

I got loads of errors for the 0805 smd resistors coz the silk lines are too thin. What I've tried: in .pcb/settings min-silk = 1.00 mil in a local pcb.settings min-silk = 6.00 mil ..saved earlier, that line uncommented and changed to 6.00 mil from the 10.00 mil before... in a bash script: #modify to taste pcb-lesstif ./tmp_pwm_p.pcb --lib-newlib ./pkg:/usr/share/pcb/newlib:/usr...


TNC connector for PCB at 1.6GHz

Started by Anonymous in sci.electronics.design9 years ago 3 replies
PCB

I'm looking for a way to add a TNC connector to our PCB. The PCB will have micro stripline or grounded coplanar waveguide circuit to which the...

I'm looking for a way to add a TNC connector to our PCB. The PCB will have micro stripline or grounded coplanar waveguide circuit to which the signal has to connect. 50ohms as usual. Most PCB connectors seem to have two wires coming from the end of the connector and I strongly suspect their matching integrity. Does anyone know of suitable connector or matching characteristics of the forem...


Low volume PCB fabrication in the Netherlands

Started by RafaP in sci.electronics.design2 years ago 14 replies
PCB

Hello, I need to find PCB manufacturer for my simple FR4 double-sided PCB prototypes. i dont find much offer on the Web. Anyone can help me...

Hello, I need to find PCB manufacturer for my simple FR4 double-sided PCB prototypes. i dont find much offer on the Web. Anyone can help me ? Thanks a lot. Cheers, Rafael


Raspberry PI model B + and 5V relay PCB

Started by gm in sci.electronics.design3 years ago 26 replies
PCB

Hi. I didnt play much with RPI but now we have finish one project where we are triggering GPIO. The PCB relay board should be triggered from...

Hi. I didnt play much with RPI but now we have finish one project where we are triggering GPIO. The PCB relay board should be triggered from RPI GPIO and the door should be opened. Now, before i connect PCB to RPI i want to be sure that nothing goes wrong. This is the pcb schematics that we use for the relay trigger. http://tinypic.com/view.php?pic=10rmrsh&s=8#.VFuEUa0zdag What do...


PCB pricing

Started by Michael in sci.electronics.design7 years ago 7 replies
PCB

I just got a quote from couple PCB houses the board is 3.3=94x1.695=94, 4 layers, 7mils spacing, FR4, two tab routs,...., 3-5 pieces, 3-4...

I just got a quote from couple PCB houses the board is 3.3=94x1.695=94, 4 layers, 7mils spacing, FR4, two tab routs,...., 3-5 pieces, 3-4 days =96 nothing unusual, right? $1200+ I sort of expected it to be ~half as much. What am I missing? has something changed in the PCB manufacturing lately?


Approximate cost of pcb assembly

Started by Bobby Joe in sci.electronics.design8 years ago 9 replies
PCB

What is the approximate cost of pcb assembly relative to pcb fabrication for low quantities? If I have 50 boards ordered at about 30$ each for...

What is the approximate cost of pcb assembly relative to pcb fabrication for low quantities? If I have 50 boards ordered at about 30$ each for pcb fab can I expect about a 1:1 cost for assembly?


PCB Turn-key Production Option

Started by Darol Klawetter in sci.electronics.design3 years ago 3 replies
PCB

Shortly I'll be moving one of my PCB designs into production. Several PCB f= ab/assembly houses offer turn key capabilities for PCB...

Shortly I'll be moving one of my PCB designs into production. Several PCB f= ab/assembly houses offer turn key capabilities for PCB manufacturing. They = handle component procurement, bare board fab, and component assembly. I wil= l perform functional testing at my facility so that is not a requirement.= =20 Who have you used? Any recommendations?=20 Thanks, Darol Klawetter


Combining single layer pcb's

Started by Jon Slaughter in sci.electronics.design8 years ago 17 replies
PCB

I only have some single layer pcb's at the moment and would like to create some double sided for a pcb fab in a day or so. Anyone have any good...

I only have some single layer pcb's at the moment and would like to create some double sided for a pcb fab in a day or so. Anyone have any good ideas how to bond them? I doubt it is difficult and I imagine roughing up the sides will work but I rather than go down that route unless it has to be done. Will most adheasives do the trick?


Looking for pcb manufacturer and assembler

Started by eryer in sci.electronics.design7 years ago 2 replies
PCB

Hi, i'm italian and i'm looking for a pcb and assembler manufacturer able to: 1. produce 12layers pcb 2. assembly bga package 3. low cost 4....

Hi, i'm italian and i'm looking for a pcb and assembler manufacturer able to: 1. produce 12layers pcb 2. assembly bga package 3. low cost 4. good for your opinion 5. italian or european Any suggestion?


PCB routing

Started by Habib Bouaziz-Viallet in sci.electronics.design7 years ago 5 replies
PCB

Hi all ! I'm being project on a based MPC8315E. I have some experience on High Speed PCB routing (DDR & DDRII) but never PCI-e or SATA. I...

Hi all ! I'm being project on a based MPC8315E. I have some experience on High Speed PCB routing (DDR & DDRII) but never PCI-e or SATA. I would be very grateful if someone could recommend me a book on the topic and generally speaking on High Speed PCB guidelines (and theory) Best regards, Habib.


gluing pcb to wood

Started by DonMack in sci.electronics.design6 years ago 36 replies
PCB

Can a pcb with standard conformal coating be glued to wood effectively? Or will the conformal coat weaken the bond? It doesn?t need to be...

Can a pcb with standard conformal coating be glued to wood effectively? Or will the conformal coat weaken the bond? It doesn?t need to be extremely strong but I need it where you can't pull it off with your hands or would be very difficult. I should also be able to remove the pcb from the wood if necessary using some flat tool like a scraper or blade(almost prying it off). So basica


max FR4 PCB temperature and lifetime

Started by Klaus Kragelund in sci.electronics.design8 years ago 5 replies
PCB

Hi UL has a rule for maximum temperature on a PCB at 105 degrees C. Standard FR4 can handle 130 degrees, and normally I have used...

Hi UL has a rule for maximum temperature on a PCB at 105 degrees C. Standard FR4 can handle 130 degrees, and normally I have used 95 degrees as a maximum to have long lifetime of the PCB (discolouration and delamination of the FR4) I have tried to find a graph of lifetime versus PCB temperature, but to no end. Have any of you ever seen one? Thanks Klaus


Thermal Conducting "epoxy" for medium power pcb

Started by Jon Slaughter in sci.electronics.design9 years ago 12 replies
PCB

Is there some type of non-electrical epoxy that can encase a pcb to remove heat? (something like a large heatsink(although not necessarily as...

Is there some type of non-electrical epoxy that can encase a pcb to remove heat? (something like a large heatsink(although not necessarily as good) that you can just form around a pcb? The reason I ask is that I've seen some circuits encased in this epoxy like block(all you see is some connectors) and I'm trying to figure out if its for heat reasons or they just don't want people to get...


how to surface mount PCB

Started by panfilero in sci.electronics.design9 years ago 5 replies
PCB

Hello, I need to create a PCB layout for a surface mount design and was wondering if someone could point me in the right direction for...

Hello, I need to create a PCB layout for a surface mount design and was wondering if someone could point me in the right direction for getting started.... I've never worked with surface mount anything before. My only experience with laying out a PCB is using expressPCB software a while back and their 3 boards for 59 bucks option. But these were for regular DIP components. Now I have tw...