Datasheet Filter Cap SF1 For Humidity and Temperature Sensor Protection against dust and particles Protection against water immersion Designed to match on SHT1x SMD type sensors Optimized on response time of sensor Product Summary The Filter Cap is made of a single piece of Polypropylene The Filter Cap SF1 protects SHT1x humidity and temperature sensors against dust, water immersion and (PP) and a filter membrane welded to the single piece. The Filter Cap is designed to be mounted after soldering consequent condensation, as well as against by sticking two pins into holes in the PCB and welding it contamination by particles. The cavity inside is made such that the volume between membrane and sensor is kept from back side. Together with the sensor it provides a compact entity which may serve as an adaptor to the minimal and hence the impact on response time for humidity measurements is reduced to a minimum. The device housing. Adding adhesive for seal to PCB and using an O-ring it provides a waterproof mounting Filter Cap is available in white color. solution. Dimensions Technical Specifications Filter Membrane 2x 1.5 Parameter Value Body material Poly Propylene (PP) Filter material PTFE with polyester scrim Color White Operating Range -40 100C Filter pore size 1.5m 1 Filtration efficiency 99.99% 2 Oleophobic Rating 6 (Scale from 1 10) 4.2 6.4 Mullen Hydrostatic 70kPa, 7m water column 10.1 RoHS Compliant 92 Packaging Filter Caps SF1 are supplied in stackable plastic trays at 100 units per tray. 4 trays are packed into a bag. Product Packaging Quantity Order Number 4.9 3.2 Filter Cap SF1 Plastic Trays 100 1-100188-01 Figure 1: Drawing of Filter Cap SF1. Dimensions are given in mm (1mm = 0.039inch), tolerances are 0.1mm for dimensions <6mm and 0.2mm for dimensions >6mm. Cavity inside the cap 1 0.1m particles at 0.05m/s air flow. fits perfectly to SHT1x sensors. Additional cavities for solder 2 Repellence of oil and hydrocarbons according to AATCC joints are left open at each side. standard. Rating 6 means n-Decane is repelled. www.sensirion.com Version 2.0 January 2009 1/3 9.4 3.7 2.0 3.7 2.5 4.7 3.7 Users Guide Filter Cap SF1 Mounting Instruction around the black cap and on the PCB around the sensor before mounting the Filter Cap. Make sure environment is The Filter Cap SF1 is mounted to the PCB after soldering well ventilated while adhesive is curing. Adhesive must be SHT1x sensor by sticking the two pins into two openings in of high viscosity to prevent it from entering the sensor the PCB. The Filter Cap may be fixed by adhesive or by protection cap. melting the pins from the back side by heating them up to If corrosion of the solder contacts is a potential problem at least 160C by a hot iron or equivalent compare then cover the solder joints well with adhesive. Figure 2. o-ring membrane Mounting against housing wall The Filter Cap SF1 not only protects against dust, water housing immersion and large organic molecules, it also helps to mount the sensor to the housing wall. If mounted to a housing wall towards the outside, the sensor is perfectly SHT1x exposed to the environment of which humidity and temperature shall be measured. PCB In order to protect the inside of the device housing against water immersion it is recommended to place an o-ring Melted plastic pin between Filter Cap and housing wall compare Figure 2. Please make sure that the housing provides an open rim Figure 2: Side view of SF1 Filter Cap mounted between PCB for the o-ring however, specify it tightly to guarantee and housing wall. Volume below membrane is kept minimal. hermetic seal. Dimension and arrangement of the openings in the PCB For such o-rings Sensirion recommends the following are given in Figure 3. Please note that openings must be specifications: wider than pins of cap to compensate for placing tolerance of sensor. Inner diameter: 6mm 2x 1.7 Cross section: 1mm Filter Cap dimension Material: NBR O-rings are provided for example by Busak & Shamban part number OR1000600. Important: Please ensure that the air path to the measured volume is not blocked by another membrane. This may increase response time of the sensor dramatically. Labeling of the shipment Each shipment is labeled with product and tracking information compare Figure 4. 1.8 3.48 1.8 7.08 0.15 0.15 Figure 3: PCB layout of SHT1x and Filter Cap SF1. Dimensions Part Description: Filter Cap SF1 are given in mm (1mm = 0.039 inch). Active pads are the ones Customer P/N: 1-100188-01 on the left side right side pads may be left floating. Quantity: 100 Pcs Lot No.: WXXXXXXX Measures for higher protection Production Date: MM/DD/YYYY For hermetic seal, adhesive must be added between Filter Figure 4: Label on shipment packaging: Customer P/N refers to Cap, sensor housing and PCB. Such seal provides higher the Sensirion product number, Lot No. refers to suppliers security against water leakage, condensation inside the tracking information. Production Date is given as MM = month, housing, and corrosion of the soldering pads of the sensor. DD = day, YYYY = year. Apply the adhesive on the FR4 substrate of the sensor www.sensirion.com Version 2.0 January 2009 2/3 6.67 1.45 0.8 No copper in this field 1.27 1.27 1.27 7.50