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 Nov 4, 2005 |
... to profile. If we program an air temperature ramp up of 4 degrees C/second to a soak temperature of 180C, stay there for 60 seconds then ramp up at the same rate to 240C and stay there for 50 seconds whether its the first or the tenth profile, the air temperature curve will be the same regardless of temperature of the metal inside . . . heater will turn on and off intermittently to maintain your profile settings. I will say that the starting air temperature inside the oven during your second and ...
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Dec 22, 2004 |
... rather than temperature. This requires a much higher level of operator skill because it is so easy to burn the boards when using IR. Shadowing is an issue that occurs with IR systems. If the light source does not hit the board evenly then the heat will not be evenly distributed throughout the board and or the component. This can cause a number of problems with BGA�s including land-sliding, bridging and component warping, which can result in open circuits. The HOT AIR temperature control is ...
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Aug 27, 2005 |
... still a good read. I was actually surprised that to test temperature uniformity across the zone, they attached T/C's to the substrate rather than measure the air temperature. By reading the temperature values on the board, it seems that they are getting closer tolerances than if they were reading the air temperature of the zone. I think they advertise/d temperature uniformity within 2 degrees. Always thought that's the air temperature tolerance within the zone . . . guess not. As far as them ...
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Aug 13, 2001 |
... four distinct temperature ramp rates in ovens that are primarily convection. TENT: two distinct temperature ramp rates in ovens that are primarily convection. You appear to be using a traditional profile. Typical temperature control times of a reflow profile are: PREHEAT TIME: Time from when the profile starts and the beginning of the ramp to peak temperature. SOAK TIME: Portion of Preheat Time prior to the beginning of the ramp to peak temperature when the temperature change is small. LIQUIDOUS ...
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Dec 5, 2001 |
... high"? As a side, the temperature on the temperature sensor is: * Inaccurate. * Not the temperature at the solder. Listen, operators are smart people. They have figured-out that they can solder faster with a hotter iron that they can with a cooler iron. There are many different working temperatures. Our operators determine working temperatures according to the alloy of the solder and the size of the joint being soldered. Typically a smaller tip and a lower temperature can be used for small ...
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Dec 19, 2007 |
... of low temperature material will disfigure and become useless at 125*C bake temperatures. The reason you can not find 70*C bake data is: J-STD033B, "4.2.2 Low Temperature Carriers. SMD packages shipped in low temperature carriers may not be baked in the carriers at any temperature higher than 40�C. If a higher bake temperature is required, SMD packages must be removed from the low temperature carriers to thermally safe carriers, baked, and returned to the low temperature carriers. Note 1 ...
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Nov 29, 2005 |
... Y axis represents temperature in Celsius (5 degrees between 2 dashed horizontal lines and 20 degrees between solid lines). Results: ProfileCycle1- a)25C to 120C in 50 seconds b)120C to 160C in 65 seconds c)160C to 219C in 60 seconds d)Peak temperature - 219C e)5 seconds at peak temperature f)Time above 183C - 90 seconds ProfileCycle10- a)25C to 120C in 50 seconds b)120C to 160C in 50 seconds c)160C to 224C in 60 seconds d)Peak temperature - 224C e)5 seconds at peak temperature f)Time above 183C ...
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Jul 19, 2007 |
... Stainless steel shelves providing endurance and rigidity. No rust or corrosion! � Humidity Set Range 1%- 50 % Rh 3 and temperature set range 20�C - 45�C4 (Optional 60�C) provide versatility for different applications. Accurately calibrated humidity and temperature sensors ensure correct measurements. 0.1 %Rh and 0.1�C resolution of humidity and temperature display. Optional Calibration Software or precisely calibrated sensors are available for customers even hard to please. � Ready ...
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Sep 30, 2004 |
Low cost Thermocouples This is what I use: http://www.omega.com/Temperature/pdf/5TC.pdf or http://www.omega.com/Temperature/pdf/5LSC_5SRTC.pdf The 36 and 40 AWG sizes are ideal (TT insulation.) $430 for 9 thermocouples seems real high ...
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Dec 19, 2007 |
... as the low temperature carrier that you want bake at a higher temperature. One of the these extra carriers needs to be high temperature material that you'll use last. * Place the low temperature material carrier on the table so that you can see the components. * Place one of the extra carriers with cavities down, pin one notation aligned, bla bla bla on top of the low temperature material carrier. * Holding both carriers, turn them upside down. When you take the low temperature material carrier ...
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Jun 9, 2003 |
Reflow Welcome. You have selected a fascinating area to work. "What is delta temperature? Depends on what someone is talking about. Here's some possibilities: * In process equipment definition, the difference in temperature from one side of conveyor to the other. * In reflow temperature recipe development, the change in temperature between the preheat and soldering. * In soldering temperature recipe development, the difference in temperature from one side of component to the other ...
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May 5, 1998 |
... temperature and faster, but requires handling components and metal tubes and reels 2. Lower temperature and slower, but can be done with the supplers tubes and reels As an expample, page from Intel's "Packaging Databook," page 8-21 8.5.2 Rebaking of PSMCs � High Temp Bake. If the HIC indicates that the contents of the MBB have expired, then the components can be baked to desorb moisture. Two bake temperature profiles are recommended, High and Low temperature. The higher temperature ...
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Apr 7, 2009 |
... bravo 4050 to find things like: Cookson Electronics News, ISSUE #6 � SUMMER 2002, High Temperature Bravo� 4050 Reflow Oven Available: ELECTROVERT� has introduced a new high temperature reflow soldering system designed for producing lead-free circuits, hybrids, ceramics and similar processing requirements. The High Temperature BravoTM 4050 Reflow Soldering System provides a maximum temperature of 350�C, well above the 300�C to 310�C level normally required for such assemblies. �This ...
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Jun 2, 2005 |
... max||3||3||3||3 Preheat - Temperature Min (Tsmin), *C||100||100||150||150 - Temperature Max (Tsmax), *C||150||150||200||200 - Tme (min to max) (ts), seconds||60-120||60-120||60-180||60-180 Tsmax to TL - Ramp-up Rate, *C/seconds max||3||3||3||3 Time maintained above: - Temperature (TL), *C ||183||183||217||217 - Time (tL), seconds||60-150||60-150||60-150||60-150 Peak Temperature, *C||225 +0/-5||240 +0/-5 ||245 +0/-5 ||250 +0/-5 Time within 5*C of actual Peak Temperature (tP), seconds||10-30||10 ...
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Nov 4, 2003 |
... supplier. Temperature Correction All hydrometer readings must be corrected from the temperature they were read at, to the temperature the hydrometer was designed for. Most hydrometers are set to 15.6*C (60*F). Some hydrometers calibrated are to 20*C. Check any hydrometer prior to use! The difference each degree of temperature makes to the specific gravity is not constant, however approximate corrections are: For every degree the sample is above the hydrometer's calibrated temperature, add 0.001 ...
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Oct 5, 2004 |
... slope. Here's an approach to calculating slope: * Subtract the lower temperature from the upper temperature. [Temp|upper-Temp|lower] = Temp|change * Subtract the time when the lower temperature was measured from the time when the upper temperature was measured. [Time|upper-Time|lower] = Time|change * Divide Temp|change by Time|change to determine slope. Generally, people calculate slope over the entire time that the temperature is changing value, because doing that averages all the little ...
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Nov 5, 2001 |
... of these profiles seem inaccurate and unreliable Returning to your comment that Type K thermocouples �suffer from temperature cycling hysteresis at above 250� C� � * Certainly all thermocouples exhibit measurement hysteresis [A lack of voltage retraceability as the temperature decreases], what is temperature cycling hysteresis? * What happens with this temperature cycling hysteresis upon reaching the 250�C? * What are the references for these articles? * What are the implications of ...
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Jan 13, 2003 |
... of investigations concerning solder joint voiding and BGA components. * Read EP&P 10/98 says something like: ** Number of small and large voids correlate. ** Reflow time (temperature) is (are) very significant in void formation. Soak time is not a factor. *** Increasing reflow temperature increases voiding. Temperature influences void formation 8.4X times greater than reflow time *** Increasing reflow time decreases voiding ** Small voids near the base (top) of the ball, increase reflow time (60 ...
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May 17, 2007 |
... of the peak temperature; we define which product is the higher runner for this line and then with the settings for this product (already profiled with thermal couples attached to the board) we pass through the oven rider. This have six thermal couples, 3 of them are attached to a defined mass (aluminium cylinders) and the others are exposed to the ambient so the air temperature is measured and also the rate of heating for this mass is measured. We only consider peak temperature for the aluminium ...
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Jan 11, 2007 |
... melting temperature than you�re accustomed to seeing. Alternately, it's possible these problem BGA have an internal slug of metal as a heat sink that dissipates some of the heat that you supply to melt the solder. J: Adding new solder to old solder that will not reflow at normal temps cures the problem just enough to clean the old solder off or remove the component in question. R: This makes sense. Mixing an alloy with a lower liquidus temperature to a high melting temperature will lower the ...
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Aug 4, 2004 |
... in temperature can increase the water's rate of reaction with the flux. Sometimes, only a 5 degree change can make the cleaning difference. If the flux inconsistently presents itself, then the likely cause is something in the system which is varying. If temperature is varying, monitor the incoming DI water temperature. Likely the Final Rinse cascades to the wash reservoir. If the final rinse temperature drops, this will have an initial effect on the wash reservoir temperature. If it drops ...
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Aug 10, 2000 |
... considerations to be borne in mind is the glass transition temperature of the basic material, for example traditional FR4 glass epoxy laminate has a glass transition temperature between 115-135oC. During recent years more attention has been paid to the use of higher stability materials which cost more. If during the processing stages, this temperature is exceeded the material changes its state and becomes pliable, when the temperature drops the board becomes rigid again. There are a number of ...
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Jul 19, 2007 |
... Stainless steel shelves providing endurance and rigidity. No rust or corrosion! � Humidity Set Range 1%- 50 % Rh 3 and temperature set range 20�C - 45�C4 (Optional 60�C) provide versatility for different applications. Accurately calibrated humidity and temperature sensors ensure correct measurements. 0.1 %Rh and 0.1�C resolution of humidity and temperature display. Optional Calibration Software or precisely calibrated sensors are available for customers even hard to please. � Ready ...
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Jul 19, 2007 |
... Stainless steel shelves providing endurance and rigidity. No rust or corrosion! � Humidity Set Range 1%- 50 % Rh 3 and temperature set range 20�C - 45�C4 (Optional 60�C) provide versatility for different applications. Accurately calibrated humidity and temperature sensors ensure correct measurements. 0.1 %Rh and 0.1�C resolution of humidity and temperature display. Optional Calibration Software or precisely calibrated sensors are available for customers even hard to please. � Ready ...
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Aug 3, 2002 |
... the laminate be elevated to a temperature above the glass transition temperature of the resin. Stress relief may well be accomplished at the same time as increased cure is being effected, as long as a slow cool down is used. In order to prevent bow and twist, the bake and cool down should be done under low pressure or under a uniform weight. Typical bake times and temperatures for the various laminate resins are shown below: Resin Type||Tg*||Bake Temperature||Time Difunctional Expoxy||130�C ...
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Jun 16, 2006 |
Oop's Pb BGA's in a RoHS process? Hi Grant, just my opinion, I think the concern could be related to the extra temperature the BGAs have been exposed during the Lead Free Reflow Temperature. So you need to check ( data sheet) what is the max temperature and how long the Pb/BGA can withstand under such temperature without get internal delaminated. Not so easy predict the BGA reliability soldered in a wrong way like that. You should perform few SAM (Scanning Acoustic Microscope) on samples of ...
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Jul 20, 2005 |
Temperature testing Hello!! Where can I find some materials and information about temperature testing?? We have a new temperature testing chamber and i would like to know how fast product will cool down and after that how soon can I put this product to high temperature testing? How can I count a capacity per day? And how long products have to be in a chamber ...
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May 27, 2004 |
... trials are also used by machine suppliers during equipment development. Temperature Uniformity. Measure the surface temperature on an assembly or ideally on a blank laminate test board to obtain any variations across the complete conveyor belt width. This will show any peaks or low points between center or near the edge of the conveyor. Test results ideally achieved to be between 5-10*C Thermal Loading. First a temperature profile is produced as a reference using six thermocouple probes soldered ...
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Feb 21, 2002 |
... the decreased surface area will lessen the surface tension enough to minimize the effect of bridging. - As Dave F was pointing out, an accurate read of the temperature is important. This is especially true with NC. Remember with a NC, the 4 most important things when spraying are Temperature, Coverage, Temperature, and oh yeah, TEMPERATURE. For the bridging / voids, these issues may be related and hit in the following manner: - If there is enough slop in the pallet, try moving the flex away from ...
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Dec 13, 2001 |
Temperature sensitive part Contact the fabricator of this part for their recommendations. There is about as many different approaches to soldering thermistors as there is thermistors. You imply that this is a SMT style package. If that is correct, it's curious that the component cannot stand soldering temperatures. Are you confusing "operating temperature" with "processing temperature"? Although you do say that the component is damaged with soldering temperature. Is that damage permanent ...
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Jul 17, 2008 |
... Contact length the greatest impact. * Control flux density, time through preheaters, top side temperature as the board reaches the wave, temperature of the solder pot while the board is being soldered, time the board is over the solder pot [K Kuhlow] * Flux specific gravity, preheater temperature, conveyer speed, solder temperature * Two most important parameters are: solder temperature & dwell time * The most extensive study ever conducted on wave solder process control, involving 384 wave ...
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Jan 14, 2007 |
... reflow at normal temps cures the problem just enough to clean the old solder off or remove the component in question. R: This makes sense. Mixing an alloy with a lower liquidus temperature to a high melting temperature will lower the liquidus temperature of the higher melt alloy, because the new melting temperature is combination of the two liquidus temperatures of the solder alloys. ----> Yes, this is great, I just need to figure out how to get (for example sake) a "liquid form of solder" to ...
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Sep 24, 2004 |
About temperature sensitive component We're not sure what you mean by temperature sensitive components. From an assembly process stand-point, every component we use is temperature sensitive to one level or another. More specifically, some of our products use polyphenylene sulfide (PPS) capacitors, and we see delamination after going through water wash. There are many layers of the plastic film to protect the dielectric layers underneath. We had similar concerns about the delam so we have run ...
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Jun 16, 2003 |
Reflow Temperatures and speed for a 7 zone top/bot for conceptro The second one is typical. The important temperature is the temperature of the joint, not the setting of the oven. The oven setting are only important because they determine the temperature of the joint. If you set the oven to 150, that will be the temperature of the oven thermocouple, and the board itself will be less than that. How much less depends on many factors. You will need to put thermocouples on the board itself to ...
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Jul 18, 2001 |
... 250C glass transition temperature - K = natural color F resin with 110-150C glass transition temperature - L = natural color I resin with > 250C flass transition temperature - M = coloring agent or opacifier added to F resin with 110-150C glass transition temperature - N = natural color of resin - P = coloring agent or opacifier added to resin - T = natural color F resin blended with nonepoxy resins for high temperature integrity, with 170-220C glass transition temperature From the Handbook of ...
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May 15, 2001 |
Loctite Adhesive Viscosity I should have been more clear;the temperature that I indicated was measured inside the dispenser cabinet. We setup a very simple system to monitor and maintain the temperature inside the cabinet. By comparing our temperature to our production results we found our best performance to be in that temperature range. I fixed the problem by reducing the shot size (in milliseconds on the Camalot) for all shots. This produced dots that were of the same size as we normally run ...
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Nov 20, 2000 |
temperature range Hello, I have to design a PCB for which the customer have the following temperature requirements: -55degC to +85degC operating temp. -61degC to +125degC storage temp. My question is: does the FR4 material meet this conditions? Which are the parameters that shall I look for when I read the specification for the FR4 materials and how are these parameters interpretated? If the FR4 material meet these temperature conditions and also the components mounted on my PCB meet these ...
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Nov 15, 2007 |
High Temperature PCB ink Questions are: What is: * Purpose of this PCB ink? * Meaning of 'non-conductive?' * Temperature of your laser? * Reason solder mask is not the product of first choice? * Space of the unsoldered region located between soldered areas? * Maximum cure temperature of the ink ...
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Nov 3, 2007 |
micropad solder problem ? Sounds like your reflow temperature recipe is a mess. * CSP has pillow => Flux exhaused or CSP never came to peak temperature * BGA balls don't combine with the solder => Flux exhaused or BGA balls never came to peak temperature * 0402 surface looks like many tin balls piled together => Flux exhaused Start your thermal recipe with you paste supplier's recommendation, measuring temperature of the solder on the terminations of low and high mass components. Search the fine ...
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Dec 19, 2006 |
Die temperature exceed Tg temperature Our company is assembly flip chip on flex, we have new design of flip chip which die temperature will increase until 145 degree C after test run the end product, however the Tg,glass transition temperature is 148. Will this case causing any reliabilty issue or any other issue will arise ...
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Nov 5, 2005 |
... the actual air temperature and adjust the heater accordingly to maintain your profile settings. When the oven is cold, the heater stays on longer/uses more power to maintain your programmed temperature ramp. When the metal inside gets hot, the heater uses less power because it mainly heats up the air considering that metal does not absorb as much heat as before. The net result is that the air temperature still ramps up at the same rate regardless of the metal temperature. It looks like your oven ...
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Jul 19, 2004 |
... to medium thermal mass assemblies. - Ramp up from ambient temperature to peak temperature of 210�-225�C at 1�C/second. Adjust ramp up rate to minimize the differential of temperature (∆T) and thermal shock to components - Time above liquidus: 45 - 75 seconds - Cool down at 1� - 3� C/second * Pre-heat time may be required for reflowing high thermal mass assemblies to minimize the T. - Ramp up from ambient temperature to 120�C at 1� - 2�C/second - Soak at 120� - 160�C for ...
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May 18, 2004 |
Affect of Moisture on Assembled PCBs Wave Solder temperature should not cause problem to MSDs. Just in case on PBA there are very critical MSLs (ie. 5 or 5a, 6 (?!?) try to detect what is the max temperature on such MSD bodies and how long they stay under such temperature. But it schould not be a dangerous temperature level. Standard J-STD-033a can tell you more. Tnks........Gabriele
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Aug 7, 2002 |
Reflow Oven Monitoring Comments on copper plate temperature monitoring are: * Some people use this type of temperature monitoring to start the day as an element of an oven capability measurement and monitoring program. * Using a copper or other metal plate, like aluminum, or a plain piece of FR-4 eliminates interaction from the substrate design and fabrication during the temperature measurement. * Measure temperature what�s important to your process. Dunno, rail-to-rail, front-to-back, and ...
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Feb 1, 2002 |
vapour phase reflow soldering technology Yes, that's what people are thinking. The 217�C melting temperature that you mention requires a ~250�C reflow temperature. Generally, boards, legend ink, and components cannot take that temperature. Further, few ovens can produce that temperature with the process control, required in many plants ...
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Sep 7, 1999 |
... solder iron tip temperature has to be what it takes to make solder joints - number one. After that, what components will solder wet and stay alive for operational cycles. Pre-heating is a factor for some parts, and I agree with Wolfgang that there ought to be something in the data sheets concerning thermal requirements and cautions. Often there isn't. | | Earl Moon | Tip temperature is not the key element in soldering although you should always start at the lowest temperature possible. A good ...
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Jun 25, 2001 |
... situation. Do not store components at the bake temperature longer than the time required to dry out the units for use in the reflow. Long storage times at elevated temperatures can cause soldering problems and the antistatic properties of the shipping carriers to deteriorate. The issues that you mentioned are compounded by component carrier baking issues. Certain carriers can only take a low temperature bake without melting. For high temperature [125�C ] bake, you probably have to remove ...
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Feb 20, 2001 |
... Depending on the material, some trays can take a high temperature bake, while other trays, in addition to tubes, and reels, require a low temperature bake. With this later group of carriers, long storage times at elevated temperatures can cause deformation of packaging, reduced solderability of components, and deterioration of the antistatic properties of the shipping carriers. The 40�C value you see quoted for low temperature baking is derived from properties of the material used to fabricate ...
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Oct 13, 2003 |
Wave Profile IPC-7530 "Guidelines for Temperature Profiling for Mass Soldering Processes (Reflow & Wave)" As you observe, the temperature you measure will depend on what you are measuring. For instance: * Hottest temperature in the oven - air in the oven * Hottest spot on the board - PCB laminate * Coldest spot on the board - largest component or a ground plane. R Prasad talks about "Bandwidth of Profile". Where in addition to meeting the shape of the profile, the oven settings must also show a ...
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Jan 24, 2002 |
... t tell us about your solder, wave temperature profile, or the distribution of the problem. So, let�s assume the solder is near eutectic and the problem is wide spread. Wolfgang makes good points. So, let's talk a different tact. When we talk �orange peel� effect. It�s an uneven, pebbly surface somewhat resembling the skin of an orange. Temperature appears to significantly influence the appearance of solder. It seems, when the bath or reflow temperature is high, tin continues smelting ...
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