MS7912 PRESSURE SENSOR DIE (0-12 BAR) • • • • 0 to 1200 kPa range (12 bar or 174 PSI) Absolute/differential pressure sensors High linearity, small size RoHS-compatible & Pb-free1 DESCRIPTION The sensor element of the MS7912 consists of a small silicon micro-machined membrane with a Pyrex glass mounted under vacuum. Implanted resistors make use of the piezo-resistive effect. The absolute pressure sensor (MS7912A) carries a sealed vacuum reference cavity underneath the membrane whereas the differential sensor (MS7912D) has a hole in the Pyrex glass at the backside of the sensor. FEATURES • • • • • • Uncompensated pressure sensor die Output Span 150mV @ 5V Temperature Range -40°…+125°C Linearity 0.05% (typical) Small Die Size 1.72 x 1.58mm Low Cost, High reliability APPLICATION • • • For absolute or differential pressure sensor systems Engine controls Dive computers ELECTRICAL CONNECTIONS Positive output for pressure applied topside Vs+ EPI Vs+ : Supply voltage of Wheatstone bridge Epi : Connection of epitaxial layer (membrane) Out+ Out- Out- : Negative output Out+ : Positive output GND1 : Ground GND2 : Ground GND1 GND2 1 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). DA7912_003.doc 00007912636 ECN 743 May 05th, 2005 1/4 PAD OUT Vs+ Epi OutImportant remarks: MS7912 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 Out+ GND1 GND2 LAYOUT MS7912A MS7912D Bondable area = 100 x 100 um Bondable area = 100 x 100 um DA7912_003.doc 00007912636 ECN 743 May 05th, 2005 2/4 FULL SCALE PRESSURE kPa bar mbar PSI atm mm Hg m H2O Inches H2O 1200 12 12000 174 11.8 9001 122 4818 ABSOLUTE MAXIMUM RATINGS Parameter Supply voltage Storage temperature Pressure overload Symbol VS+ TS Conditions Min Max Unit -40 20 +150 30 V C Bar o Ta = 25 C o ELECTRICAL CHARACTERISTICS (Reference conditions: Supply Voltage VS+ = 5 Vdc; Ambient Temperature Ta = 25°C ) Parameter Operating Pressure Range Min Typ Max Unit 0 12 Bar Operating Temperature Range -40 125 °C Bridge Resistance 3.0 3.4 3.8 kΩ Full-scale span (FS) 120 150 180 mV Zero Pressure Offset -40 0 40 mV ± 0.05 ± 0.15 Linearity Temperature Coefficient of Resistance Span Offset + 2400 - 1500 - 80 Notes % FS 1 ppm/°C ppm/°C µV/°C 2 + 2800 - 1900 + 3300 - 2300 + 80 Pressure Hysteresis ± 0.05 ± 0.15 % FS 3 Repeatability ± 0.1 ± 0.2 % FS 4 0.3 % FS 5 Temperature Hysteresis NOTES 1) Deviation at one half full-scale pressure from the least squares best line fit over pressure range (0 to 12 bar). 2) Slope of the endpoint straight line from 25°C to 60°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°C to +125°C. DA7912_003.doc 00007912636 ECN 743 May 05th, 2005 3/4 PICKING TOOLS The MS7912 sensors have a sensitive membrane (0.5 x 0.5 mm) the top surface of the sensor dice has an outer of diameter is: 1.62 x 1.48 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 sensor and the vacuum cavity must be as large as the membrane itself. Successful test where 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 ORDERING INFORMATION Product Code Product Art.-Nr. MS7912A 1200 kPa Absolute Pressure Sensor 791225021 MS7912D 1200 kPa Differential Pressure Sensor 791225121 The MS7912 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. DA7912_003.doc 00007912636 ECN 743 May 05th, 2005 4/4