da7207-a2_000.doc april 24, 2009 1/5 000072071503 ecn 1209 MS7207-A2 pressure sensor die (0-7 bar) for harsh environment ? 0 to 700 kpa range (7 bar or 102 psi) ? uncompensated absolute pressure sensor die ? piezoresistive silicon micromachined sensor ? hermetic sensor, temperature up to 150c ? pads on one side ? rohs-compatible & pb-free 1 description the MS7207-A2 is an absolute silicon micro-machined pressure sensor for harsh environment, with the pa ds on one side. a vacuum reference cavity is sealed on to p of the sensitive silicon membrane by the anodic b onding of a glass cap. the pressure, applied on the backside, is converted in electrical signal by piezo-resisto rs implanted in the silicon membrane. to improve the sensor stab ility, a drilled glass is bonded on the backside. a s the pressure port consists of glass and silicon, both s table in most of the chemicals, the MS7207-A2 is su itable for media-resistive applications. features ? media resistive pressure sensor die ? linearity 0.15% (typical) ? typical output span 150mv @ 5 v ? die size 1.73 x 1.18 mm 2 ? temperature range -40?+150c ? low cost, high reliability & stability application ? harsh environments ? absolute pressure sensor systems electrical connections 1 the european rohs directive 2002/95/ec (r estriction o f the use of certain h azardous s ubstances in electrical and electronic equipment) bans the use of lead, mercury, cadmium, hexavalent chromium and polybrominated biphenyls (pbb) or poly brominated diphenyl ethers (pbde). pin symbol description 1 epi / i diode (-) epi contact / cathode of diode (n) 2 vs+ / i diode (+) supply voltage / anode of diode (p) 3 out+ positive output* 4 gnd ground 5 out- negative output* *positive output for pressure applied backside
da7207-a2_000.doc april 24, 2009 2/5 000072071503 ecn 1209 bond pad configuration important remarks: the epitaxial layer is not connected to the vs+ pin on the die, this is to allow temperature measurement with the diode. the epi contact and the cathode of the diode have the same electrical potential. to avoid bias effect s, diode and bridge cannot be used simultaneously. as the sensing elements are diffused resistances, t he voltage applied on the ground pads (gnd) and on the supply voltage (vs+) have to be lower or equal than the voltage applied on the epi contact (epi). for bette r stability it is good to define the potential of the epi. gold ball bonding or aluminum wedge bonding can be used to wire-bond the sensor. the quality of the wire-bo nding is equipment and process dependant. for this reason, i t is strongly recommended that a thorough wire-bonding qualification is made by the end user if the sensor is going to be operated over an extended temperature range. layout
da7207-a2_000.doc april 24, 2009 3/5 000072071503 ecn 1209 full scale pressure kpa bar mbar psi atm mm hg m h 2 o inches h 2 o 700 7 7000 101.5 6.9 5250 71 2810 absolute maximum ratings parameter symbol conditions min max unit supply voltage, bridge vs+ ta = 25 o c 12 v supply current diode i diode (+) 100 a storage temperature t s -40 +150 o c pressure overload 35 bar electrical characteristics (reference conditions: supply voltage vs+ = 5 vdc; ambient temperature ta = 25c ) parameter min typ max unit notes operating pressure range 0 7 bar operating temperature range -40 150 c bridge resistance 3.0 3.4 3.8 k full-scale span (fs) 120 150 180 mv zero pressure offset -40 0 40 mv linearity 0.15 0.3 % fs 1 diode forward voltage (v f ) 0.550 v 2 temperature coefficient of resistance span offset diode + 2400 - 1500 - 80 + 2800 - 1900 -2.2 + 3300 - 2300 + 80 ppm/c ppm/c v/c mv/c 3 2 pressure hysteresis 0.05 0.15 % fs 4 repeatability 0.05 0.15 % fs 5 temperature hysteresis 0.3 % fs 6 notes 1) deviation at one half full-scale pressure from the least squares best line fit over pressure range (0 to 2 bar). 2) the forward voltage of the diode is measured wh en driving it with a typical value of 40 a. 3) slope of the endpoint straight line from 25c t o 60c. 4) output deviation at any pressure within the spe cified range, when this pressure is cycled to and f rom the minimum or maximum rated pressure, at 25c. 5) same as 4) after 10 pressure cycles. 6) maximum difference in offset after one thermal cycle from -40c to +150c. temperature compensation the diode between the piezo diffusion and the epi c ontact can be used for temperature measurement. the forward voltage of the diode is measured on i diode (-) when a typical current of 40 a fed in i diode (+). temperature measurement cannot be done at the same time as pressure sensing due to bias effects.
da7207-a2_000.doc april 24, 2009 4/5 000072071503 ecn 1209 picking tools the MS7207-A2 sensors have a topside glass cap (1.0 5 x 1.18 mm 2 ) and a backside glass (1.73 x 1.18 mm 2 ). the pick and place tool has to be of a soft materia l such as rubber (hardness 78-97 shore a). its exte rnal size must fit the glass cap. successful tests were done with some tools of spt (see spt drawing and referen ces below). spt references rtr-a2-045x045 external dimension tl & tw: 0.045 inch /1.14 mm internal dimensions ? h: 0.025 inch / 0.63 mm wire bonding the bondable area is 100 x 100 m 2 for the epi pad and 100 x 285 m 2 for the other pads. the location of the bonding pads is close to the top pyrex glass edge r educing the possible size and angle of the bonding capillary. refer to the detail view d on the layout for more precision. ordering information product code type product art.-nr. MS7207-A2 absolute 7 bar pressure sensor die for harsh environment saw n on b/f 720725021 the MS7207-A2 dice are supplied sawn on blue foil, mounted on plastic rings
da7207-a2_000.doc april 24, 2009 5/5 000072071503 ecn 1209 factory contacts factory and european sales office intersema sensoric sa phone: +41 32 847 9550 ch. chapons-des-prs 11 fax: +41 32 847 9569 ch-2022 bevaix e-mail: switzerland website: www.intersema.ch usa measurement specialties inc. phone: +1 800 555 155 1 1000 lucas way fax: +1 757 766 4297 hampton, va 23666 e-mail: sales@meas-spec.com usa website: www.meas-spec.com asia measurement specialties (china), ltd. phone: +86 75 5 8330 1004 f1.6-4d, tian an development fax: +86 755 8330 6797 compound e-mail: pfc.cs.asia@meas-spec.com shenzhen, china 518048 website: www.meas-spec.com notice intersema reserves the right to make changes to the products contained in this data sheet in order to improve the design or performance and to supply the best possible products. intersema assumes no responsibility for the use of any circu its shown in this data sheet, conveys no license under any patent or other rights unless otherwise specified in this data sheet, and makes n o claim that the circuits are free from patent infringement. applications for any devices s hown in this data sheet are for illustration only a nd intersema makes no claim or warranty that such applications will be suitable fo r the use specified without further testing or modi fication.
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