MS7228-A

MS7228 PRESSURE SENSOR DIE (0-28 BAR) FOR HARSH ENVIRONMENT • • • • 0 to 2800 kPa range (28 bar or 406 PSI) Absolute pressure sensors Hermetic sensor RoHS-compatible & Pb-free1 DESCRIPTION The MS7228 is an absolute silicon micro-machined pressure sensor for harsh environment. A vacuum reference cavity is sealed on top of the sensitive silicon membrane by the anodic bonding of a Pyrex™ cap. The pressure, applied on the backside, is converted in electrical signal by piezo-resistors implanted in the silicon membrane. To improve the sensor stability, a drilled Pyrex™ is bonded on the backside. As the pressure port consists of Pyrex™ and silicon, both stable in most of the chemicals, the MS7228 is suitable for media-resistive applications. FEATURES • • • Media resistive pressure sensor die Output Span 150mV @ 5 V Temperature Range -40° …+125° C • • • Linearity 0.05% (typical) Die Size 1.63 x 1.95 mm2 Low Cost, High reliability APPLICATION • • • Harsh environments Absolute pressure sensor systems Braking systems • • • Tire pressure Engine controls Diving computers ELECTRICAL CONNECTIONS Positive output for pressure applied backside Vs+ : Supply voltage of Wheatstone bridge Epi : Connection of epitaxial layer (membrane) Out- : Negative output Out+ : Positive output GND1 : Ground GND2 : Ground GND1 1 Vs+ EPI Out+ Out- GND2 The European RoHS directive 2002/95/EC (Restriction of the use of certain Hazardous Substances in electrical and electronic equipment) bans the use of lead, mercury, cadmium, hexavalent chromium and polybrominated biphenyls (PBB) or polybrominated diphenyl ethers (PBDE). DA7228_001.doc 000072281161 ECN 1145 October 6, 2008 1/4 PAD OUT MS7228 Out- Vs+ Important remarks: As the sensing elements are diffused resistances, the voltage applied on the ground pads (GND1 and GND2) has to be lower than the voltage applied on supply voltage pad (Vs+). The epitaxial layer is connected to the Vs+ pin on the die. GND1 Epi GND2 Out+ LAYOUT DA7228_001.doc 000072281161 ECN 1145 October 6, 2008 2/4 FULL SCALE PRESSURE kPa 2800 bar 28 mbar 28000 PSI 406 atm 27.5 mm Hg 21002 m H2O 285 Inches H2O 11242 ABSOLUTE MAXIMUM RATINGS Parameter Supply voltage Storage temperature Pressure overload Symbol VS+ TS Ta = 25 C -40 o Conditions Min Max 20 +150 70 Unit V C Bar o ELECTRICAL CHARACTERISTICS (Reference conditions: Supply Voltage VS+ = 5 Vdc; Ambient Temperature Ta = 25° ) C Parameter Operating Pressure Range Operating Temperature Range Bridge Resistance Full-scale span (FS) Zero Pressure Offset Linearity Temperature Coefficient of Resistance Span Offset Pressure Hysteresis Repeatability Temperature Hysteresis NOTES Min 0 -40 3.0 100 -40 Typ Max 28 125 Unit Bar ° C kΩ mV mV % FS ppm/° C ppm/° C µV/° C % FS % FS % FS 1 2 Notes 3.4 130 0 ± 0.05 3.8 160 40 ± 0.15 + 3300 - 2300 + 80 ± 0.15 ± 0.15 0.3 + 2400 - 1500 - 80 + 2800 - 1900 ± 0.05 ± 0.05 3 4 5 1) Deviation at one half full-scale pressure from the least squares best line fit over pressure range (0 to 28 bar). 2) Slope of the endpoint straight line from 25° to 60° C C. 3) Output deviation at any pressure within the specified range, when this pressure is cycled to and from the minimum or maximum rated pressure, at 25° C. 4) Same as 3) after 10 pressure cycles 5) Maximum difference in offset after one thermal cycle from -40° to +125° C C. DA7228_001.doc 000072281161 ECN 1145 October 6, 2008 3/4 PICKING TOOLS The MS7228 sensors have a topside Pyrex™ cap (1.23 x 1.02 mm ) and a backside Pyrex™ (1.95 x 1.63 mm ). The pick and place tool has to be of a soft material as rubber (Hardness 78-97 Shore A). Its external size must fit the Pyrex™ cap. Successful tests were done with some tools of SPT (see SPT drawing and references bellow). SPT references External dimension Internal dimensions RTR-A1-060x060 TL & TW: 0.06 inch /1.52 mm ∅H: 0.035 inch / 0.89 mm 2 2 WIRE BONDING The bondable area is 100 x 100 µm . The location of the bonding pads is close to the top Pyrex glass edge reducing the possible size and angle of the bonding capillary. Refer to the detail view D on the layout for more precision. 2 ORDERING INFORMATION Product Code MS7228-A type Absolute Product 28 bar Pressure Sensors sawn on b/f Art.-Nr. 722825021 The MS7228 dice are supplied sawn on blue foil, mounted on plastic rings FACTORY CONTACTS Intersema Sensoric SA Ch. Chapons-des-Prés 11 CH-2022 BEVAIX SWITZERLAND Tel. 032 847 9550 Tel. Int. +41 32 847 9550 Telefax +41 32 847 9569 e-mail: http://www.intersema.ch 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 circuits shown in this data sheet, conveys no license under any patent or other rights unless otherwise specified in this data sheet, and makes no claim that the circuits are free from patent infringement. Applications for any devices shown in this data sheet are for illustration only and Intersema makes no claim or warranty that such applications will be suitable for the use specified without further testing or modification. DA7228_001.doc 000072281161 ECN 1145 October 6, 2008 4/4