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Oct 24, 2018 | Shenzhen Vip Circuit Co.,Ltd is the professional PCB and PCBA manufacturer in China. 1. PCB business include the general PCB and special process PCB such as HDI, high frequency, aluminum base, heavy copper, golden finger, blind via, flex or rigid-flex; 2. PCB urgent service :1L or 2L within 24
Apr 19, 2017 | high-frequency PCB circuit design Hey Westen, we have an article about misunderstandings and strategies on High-Speed PCB design, you might find some valuable info. Article address: http://www.pcbcart.com/article/content/high
Apr 18, 2017 | Hi , I have some documents on IPC satandard regarding the design , may can help you.
Apr 5, 2017 | high-frequency PCB circuit design Excellent document link you have shared. High Frequency signals reflected on circuit board, meaning that the impedance (dynamic resistance) varies with respect to the sending component.
Apr 5, 2017 | high-frequency PCB circuit design Excellent document link you have shared. High Frequency signals reflected on circuit board, meaning that the impedance (dynamic resistance) varies with respect to the sending component. Multi PCB supports you starting immediately in the design phase.
Mar 7, 2017 | Hi Westen, Yes, lots of things cause problems on an physical PCB compared to a simulated PCB. Noi
Mar 7, 2017 | high-frequency PCB circuit design Hi, I wonder if you can kindly give me advises on high-frequency PCB circuit design.It seems that some aspects need to be paid attention.Thanks a lot!
Sep 9, 2016 | if it's high frequency then you actually don't really care about the void at all.
Aug 4, 2016 | high speed PCB frequency range Here is a video for high speed pcb design rule and techniques. https://www.youtube.com/watch?v=BlHLmQ2HO1w This may help you.
Aug 2, 2016 | I think it is normally from 4.0 to 5.0
Jun 11, 2016 | high speed PCB frequency range IPC-2252 - Design Guide for RF/Microwave Circuit Boards IPC-2251 - Design Guide for the Packaging of High Speed Electronic Circuits IPC-2141A - Design Guide for High-Speed Controlled Impedance Circuit Boards IPC design standards https://portal.ipc.org/Purchase/CatalogSearchResults.aspx?Option=1
Jun 11, 2016 | high speed PCB frequency range i'm new to pcb design and i'm wondering that starting from which frequency range we need to apply the high speed PCB design rules and techniques ?
Apr 30, 2016 | .24 hours turn time on double sides PCB's,3-7 days for multilayer PCB's. 6.Producing over 5,000 unique part numbers per month ,Monthly capacity exceed 70,000 square meters. 7.Exceed 3000 employees,Annual sales exceed $150 million. 8.Covering the 2-14 Multilayer PCB Prototype,HDI PCB,High Frequency PCB High Mix,Low Volume,Short Delivery PCB Supplier. 1.The world top 500 PCB supplier.( Samsung DELL Alcatel-Lucent Huawei Lenovo FOXCONN ASUS etc ) 2.Over 15+ Years of PCB Expertise. 3.Provided "PCB & Assembly One-stop shop"service,No MOQ. 4.ISO9001 ISO14001 TS16949 Certified & UL Approved. 5
Jul 9, 2015 | Hello Maxim, we offer below services with Popular Competitive Pricing: －Express PCB Prototyping(2-28 layer) －HDI PCB －Flexible Printed Board(1-8 layer) －Flexi-rigid Printed Board －High Frequency Board(Rogers,Arlon,PTFE) －Blind/Buried Via Board －High Tg Thick Copper PCB (Up to 6oz with TG180
May 14, 2015 | I like MpM personally - run forever and programming is easy and leads you through it. It's hard to miss a step of programming with MpM software. DEK's a little harder (for me) but still very nice controls. The pluses of DEK - DEK has a high frequency vibro system (can't remember the name of it
Nov 20, 2014 | . 2* with the core elements of each functional circuit as the center, around it to layout. Components should be uniform, neat, compact arrangement in PCB. Minimize and shorten the lead between each component and connection. 3* circuit in high frequency, to consider the distributed parameter between
Aug 4, 2013 | At this low frequency there is little need to worry about frequency related effects in your PCB related layout. regards sarason
Jun 5, 2012 | Profile Frequency Thanks for your inputs guys, I will take them in consideration to define the frequency, regards!
Aug 8, 2011 | SMT Design Issues for 2225 Capacitors in High Power RF We are building a plasma diagnostic to monitor MHD phenomena in tokamak. As part of the development, we need high-voltage, high-power RF capacitors to tune and match an inductive load. This application is similar to a small induction heater, with the following operational parameters: RF Power 2 -4 kW Frequency 50-300 kHz RF Voltage 500-1000 V RF Current 50-100 A Duty Factor would be 10 second pulses 10 minutes apart with continuous operation at lower power for testing and calibration. We need to build two digitally adjustable capacitors (0.6-5.0 uF and 0.1-9.0 uF) out of smaller surface
Aug 23, 2010 | Similar to Coop's comments, above ... Bridging: * Mis-placement: misplaced components, high placement force mushrooms paste * Too much paste: HASL thickness, lead finish, poor underside support, poor underside wipe frequency, printing with too large a snap-off, poor stencil design / manufacture , board warp, poor stencil gasketing, high squeegee down-force * Paste slump: paste quality, too much time between print and reflow, poor reflow profile * Misprinted paste
Jul 6, 2010 | Hi, I have seen the oscillation frequency change in higher humidity environments. Was doing some data acquisition in a high humitity environment in 1990 using some off the shelf loggers. The data that was collected was incorrect. Found out the crystal was oscillating at the wrong frequency . To fix the problem I cut the can off the leaded crystal. I know sounds like it would get worse but indeed it improved. Moisture was not longer trapped in the crystal can and thus it oscillated at the correct frequency.
Oct 14, 2009 | PCBA fail functional test due to frequency drift We found a PCBA performance have insertion loss at the functional test process. We did some analysis and conclude the main root cause is from the PCB performance. What is the critical parameter in PCB will cause a failure in PCBA frequency performance?
Mar 2, 2009 | High complex board manufacturing with up to 10% reduction, seriously consider Stencil Thickness from 4.5 Mils to 5.5 Mils. 4. Though Your Process has to run with Manual Stencil Cleaning, set the frequency as low as 4 to 5 Print Cycles. Use Ethanol / Iso Profile Alcohols with Lint-free cloth to clean Stencil foil. Though Aperture openings are optimized 16 Mils, set a frequency to use Air/Brush Cleaning at QFPs, TSSOPs, CSPs & �BGA Locations to ensure no Aperture Blockage. 5. Ensure 100% Placement Accuracy at Pre Reflow specially at 0402 Chips to avoid Over Hangs / Tomb-stoning. 6. Stick to Ramp Soak Spike(RSS)/Low Long Spike (LLS) Type Reflow
Jul 16, 2008 | Thermal Profiling Frequency System > Armynski, > > You should do a Cpk study to > baseline how capable your ovens are. Then based > on Cpk, determine the frequency. nice input!
Jul 16, 2008 | Thermal Profiling Frequency System Armynski, You should do a Cpk study to baseline how capable your ovens are. Then based on Cpk, determine the frequency.
Jul 15, 2008 | How many times do you measure your oven's profile? I have seen companies running a thermal profile prior to every run of their products into the oven. But if you are in a low to medium volume - high mix category what is the best frequency of measurement for each product? I am looking at the angle Thermal Profiling Frequency System
Jul 9, 2008 | to alloys then no stainless steel!) and anything containing arsenic. Well LEDs all have GaAs in them, and so do a number of high frequency chips, as used in cell phones. So, if the worst-case scenario is actually intended in that report, your whole modern kitchen with all the stainless-sheathed appliances
Feb 19, 2008 | soldering, to show the difference in the ionic contamination. It should be low enough to not effect his impedences. Although, I will say that I've heard of cases of high frequency RF boards having super-sensitivity to ionic contamination. Cheers ..rob
Nov 8, 2007 | don`t we have any article about the manufacturing of high frequency board . and precautions that we should use ?
Nov 5, 2007 | solder paste alloy effect on high frequency board "Effects of surface finish on high frequency signal loss using various substrate materials" - Call Don Cullen at Mac Dermid or Larry Gatewood at Rockwell Collins for a copy.
Nov 4, 2007 | solder paste alloy effect on high frequency board can you send me the articles about the high frequency boards issues with different types of solder paste alloy because i can`t find any free document about this article
Nov 4, 2007 | we are manufacturing some rf boards that works on a high frequency margins now our boards doesn't pass in impedance test and we concluded that the problem might cause by the solder paste that we are using . our solder alloy is sn62/pb36/ag2 and we think that it might be form the AG2 that is used
Oct 11, 2007 | Lots of papers out there on HiFreq circuits and the effects of solder paste residue. Google Dr. Kare
Oct 10, 2007 | I have always understood that on boards (or circuits) operating over 900 MHz, No Clean fluxes are to
Oct 10, 2007 | Does it fail to function or does it function outside of acceptable tolerances? If the latter I w
Oct 10, 2007 | everything else EXACTLY the same? meaning exact same product number from the same manufacturer same
Oct 10, 2007 | solder paste alloy effect on high frequency board hi we use a no clean solder paste with the sn63pb37 alloy and our high frquency board doesn`t have any problem in test but after this product is finished now we use 2 different solder pastes 1. sn62 pb36 Ag.4 RA tape 2. NC type lead free with Ag in the alloy and now our high frequeny board doesn
Jul 11, 2007 | is the preferred and most efficient mechanical scrubbing action, manual cleaning and spray-under-immersion using 440-R SMT Detergent is also safe and effective. Q: What are the differences between ultrasonic �Frequency� and �Power Density�? A: The lower the ultrasonic frequency, the more powerful the scrubbing action. Common ultrasonic cleaning frequencies range from 20 kHz up to around 68 kHz (frequencies above 68 kHz are available, but rare and very costly). Using the analogy of manual cleaning with a scrub brush, the ultrasonic �frequency� is similar to the type of brush used. Using a 20 kHz frequency would be like using a �wire� brush. Using a 68 kHz frequency would be like using a tooth brush. Most stencil cleaners use a frequency of 40 kHz and modulate or �sweep� the frequency +/- two kHz to eliminate standing waves or �hot spots� in the cleaning bath. Ultrasonic �Power Density� is the amount
Feb 5, 2007 | Thank you Dave...always helpful....
Feb 5, 2007 | While you're waiting for others to reply, look here:
Feb 5, 2007 | Good morning,
What is considered "high frequency" ,.i.e. Mhz,GHz,etc., when we talk about possible issues with NO-clean flux residues and product's application?
I appreciate your help on this...
Have a good one!
George No-clean flux and high freq. applications?
Feb 5, 2007 | Good morning, What is considered "high frequency" ,.i.e. Mhz,GHz,etc., when we talk about possible issues with NO-clean flux residues and product's application? I appreciate your help on this... Have a good one! George No-clean flux and high freq. applications?
Feb 5, 2007 | No-clean flux and high frequency? Hello everybody, What is considered "high frequency" when we talk about possible issues with NO-clean flux residues and product's application? I appreciate your help on this... Have a good one! George
Jan 5, 2007 | I am using PWB material Rogers 6002 High Frequency Laminate. The PWBs are assembled. They were washed and will require a bake out. Some people say, no bake out is required for the material. I am getting different reads in test if the CCAs are not baked to remove the moisture. Can anyone tell
Dec 14, 2006 | Hi, where can I find info about how to make the pad design to work for VSSOP48 0.4 mm Pitch & TSSOP56 0.5 mm pitch components? I should also mention that we are working in a project that this 14 layers High-Frequency RoHS board is included. The pad capacitance and conductance of ours is critical
Oct 5, 2006 | to the fact that PCB is desing for high frequency. Regards David
Aug 11, 2006 | Hi, We have a issue with current leakage between pins on an SSOP 28 in a low frequency RF application and there is a suspicion that it is being caused by something in the flux residue. We have had the bad boards analyzed and a 'high' Chloride level was found. Does anyone have some data on what
Jul 24, 2006 | Here are some additional comments that have been posted on the CircuitNet web site: Fist, the answer is the same regardless of the specific paste type, (leaded or non-leaded). High pressure sprays should never be applied to a stencil. Stencils are relatively delicate and should not be exposed to either high pressures or high temperatures. The application of ultrasonic energy (sound waves) is considered by experts to provide thorough cleaning while avoiding any damage potential. Mike Konrad, President Aqueous Technologies ________________________________________ A great question with a simple answer. In my experience, ultrasonics do a much better job of cleaning the stencils than high-pressure jets. Ultrasonics impart far more energy into the contamination through the solvent than any high-pressure spray could generate. Some tests have found collapsing cavitation can generate up to 10
Jul 17, 2006 | ="_blank">http://www.smartsonic.com/article.html) Mr. Kenyon stresses the importance of High Ultrasonic Frequency and Low Power Density when cleaning PCBs. Using the analogy of scrubbing with a brush, the Ultrasonic Frequency = the type of brush and the Power Density = the amount of pressure used on the brush. Common ultrasonic frequencies range ). Low ultrasonic frequency (20 kHz) = a wire scrub brush High ultrasonic frequency (68 kHz) = a soft tooth brush Low power density = holding the brush lightly with one hand High power density = holding the brush strongly with two hands The Power Densities of stencil cleaners can vary tremendously -free stencils? What type of stencil cleaner is preferred: ultrasonic or high pressure jet? The application is in lead free cleaning of stencils after screen printing. Ask the Experts Comments: ---------------------------------------------------------- This is a good opportunity to let everyone know
May 9, 2006 | bridging recommendations are chalk. Regardless, they better than anything else the fine folk here have offered. * Mis-placement: misplaced components, high placement force mushrooms paste * Too much paste: HASL thickness, lead finish, poor underside support, poor underside wipe frequency, printing with too large a snap-off, poor stencil design / manufacture, board warp, poor stencil gasketing, high squeegee down-force * Paste slump: paste quality, too much time between print and reflow, poor reflow profile * Misprinted paste * Poor gasketing * Inadequate under stencil cleaning
Mar 28, 2006 | Hi Rob, They want you to think that their products are subtly different & that they are not interchangeable, although they are in nearly all cases (this is different for high frequency RF design). Also your layout guys aren't going to love you with a plethora of footprints for each case size
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