? freescale semiconductor, in c., 2006. all rights reserved. AN3150 rev 1.0, 2/2006 freescale semiconductor application note soldering recommendations for pressure sensor devices by: bill mcdonald introduction pressure sensor devices require the internal cavity containing the silicon transducer to be exposed to ambient in order for the device to function. exposed cavity packages require special considerations during board assembly to prevent damage to the device during soldering and subsequent cleaning operations. figure 1. basic element figure 2. port adapter surface mount components components can be mounted using solder paste stencil, screen printed or dispensed onto the pcb pads prior to placement of the component. the volume of solder paste applied to the pcb is normally sufficient to secure the component during transport to the subsequent reflow soldering process. use of adhesives to secure component is not recommended, but where necessary can be applied providing the vent at the underside of the package does not become blocked. this is applicable only to a gauge pressure sensor device. absolute pressure sensor devices do not have a backside vent so vent blocking is not an issue. solder pastes are available in variety of metal compositions, particle size and flux types. the solder paste consists of metals and flux required for a reliable connection between the component lead and the pcb pad. flux aids the removal of oxides that may be present on pcb pads and prevents further oxidation from occurring during the solder process. the use of a no-clean (nc) flux is recommended for exposed cavity components. using pressure spray or other methods of cleaning is not recommended. if cleaning of the pcb is performed water soluble (w s) flux can be used, but it is recommended the component ca vity to be protected by adhesive kapton tape, vinyl cap or other means prior to the cleaning process to prevent contamination and foreign materials from being introduced into device cavity as result of cleaning processes. refe r to this link for info. http://www.stockcap.c om/products.asp ultrasonic cleaning is not recommended as the frequencies can damage wire bond interconnections. reflow soldering is typically used for surface mount components and accomplished by convection heat from the sides of the reflow furnace utilizing air circulation to produce uniform temperature across the pcb. hot spots and shielding of the smaller components by adjacent larger components can be minimized thus achieving more reliable solder connection.
AN3150 sensors 2 freescale semiconductor through-hole (dip) style components dual in-line and other styles of through-hole components packages are typically wave soldered where the leads protrude through the circuit board and exposed to a flux bath then immersed into molten solder as the board is passed over a solder wave to create the solder connection. in this application the top board surf ace and component body are not directly exposed to high temperatures. soldering precautions wave solder does not typically expose component to excessive temperature, but there may be cases where components are subjected to secondary reflow cycle during double side board assembly. vapor phase soldering process is not recommended for open cavity devices. there is a potential for liquid to ingress into the cavity or possibility of condensation to form in cavity of the device. ir reflow is not recommended due to potential damage to plastic features as result of radiation heat transfer. mpxa, mpxh, mpxm and mpxv series pressure sensors with port adapters should not be exposed to temperatures greater than 245c. suffix designations for these devices are; c, ap, dp and gsx. mpx series pressure sensors with port adapters should not be exposed to temperatures greater than 220c. the suffix designations for these devices are; ap, gp, dp, as, gs,asx or gsx. refer to the following table for listing of device types and recommended maximum temperature exposure. the reflow temperature profile for surface mount devices must be in accordance with jedec std. 020. refer to following link for specific profile details. http://www.jedec.org/dow nload/search/jstd020c.pdf devices provided with a mounting bracket for special applications are to be excluded.
AN3150 sensors freescale semiconductor 3 rework of soldered components rework is not recommended, but should it be necessary, ma ximum temperature exposure for devices should not exceed the limits shown in table 1 with minimized duration. table 1. pressure sensors device number suffix designation package maximum temperature c mpx a,d basic element 245 ap port adapter 220 gp port adapter 220 dp port adapter 220 as port adapter 220 gs port adapter 220 asx port adapter 220 gsx port adapter 220 mpxa a basic element 245 c port adapter 245 gsx port adapter 245 mpxv g basic element 245 c port adapter 245 dp port adapter 245 gp port adapter 245 gvp port adapter 245 gsx port adapter 245 mpxh a basic element 250 c port adapter 250 mpxm a,d basic element 250 as,gs port adapter 250
AN3150 rev 1.0, 2/2006 information in this document is provided solely to enable system and software implementers to use freescale semiconduc tor products. there are no express or implied copyright licenses granted hereunder to design or fabricate any integrated circuits or integrated circuits based on the information in this document. freescale semiconductor reserves the right to make changes without further notice to any products herein. freescale semiconduc tor makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does freescale semiconductor assume any liability ar ising out of the application or use of any product or circuit, and specifically discla ims any and all liability, including without limitation consequential or incidental dam ages. ?typical? parameters that may be provided in freescale semiconductor data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. all operating parameters, including ?typicals?, must be validated for each customer application by customer?s technical experts. freescale semiconductor does not convey any license under its patent rights nor the rights of others. freescale semiconductor products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applic ations intended to support or sustain life, or for any other application in which the failure of the freescale semiconductor product could create a situation where personal injury or death may occur. should buyer purchase or use freescale semiconductor products for any such unintended or unauthorized application, buyer shall indemnify and hold freescale semiconductor and its officers, employees, subsid iaries, affiliates, and dist ributors harmless against all claims, costs, damages, and expenses, and re asonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim alleges that freescale semiconductor was negligent regarding the design or manufacture of the part. freescale? and the freescale logo are trademarks of freescale semiconductor, inc. all other product or service names are t he property of their respective owners. ? freescale semiconductor, inc., 2006. all rights reserved. how to reach us: home page: www.freescale.com e-mail: support@freescale.com usa/europe or locations not listed: freescale semiconductor technical information center, ch370 1300 n. alma school road chandler, arizona 85224 +1-800-521-6274 or +1-480-768-2130 support@freescale.com europe, middle east, and africa: freescale halbleiter deutschland gmbh technical information center schatzbogen 7 81829 muenchen, germany +44 1296 380 456 (english) +46 8 52200080 (english) +49 89 92103 559 (german) +33 1 69 35 48 48 (french) support@freescale.com japan: freescale semiconductor japan ltd. headquarters arco tower 15f 1-8-1, shimo-meguro, meguro-ku, tokyo 153-0064 japan 0120 191014 or +81 3 5437 9125 support.japan@freescale.com asia/pacific: freescale semiconductor hong kong ltd. technical information center 2 dai king street tai po industrial estate tai po, n.t., hong kong +800 2666 8080 support.asia@freescale.com for literature requests only: freescale semiconductor literature distribution center p.o. box 5405 denver, colorado 80217 1-800-441-2447 or 303-675-2140 fax: 303-675-2150 ldcforfreescalesemiconductor@hibbertgroup.com rohs-compliant and/or pb-free versions of freescale products have the functionality and electrical characteristics of thei r non-rohs-compliant and/or non-pb-free counterparts. for further information, see http://www.freescale.com or contact your freescale sales representative. for information on freescale?s environmental products program, go to http://www.freescale.com/epp .
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