Very Fast Humidity Sensor for Radiosondes HC103M2 is a capacitive humidity sensor with very short response time even at very low temperature. By this, the sensor is ideal for accurate measurement in the upper atmosphere with radiosondes and weather balloons. The sensor is manufactured in state of the art thin film technology and is appropriate for SMD assembly. The design and the choice of materials lead to excellent linearity, high sensitivity and reproducible temperature dependence, which facilitate considerably the design in. HC103M2 is supplied on tape and reel appropriate for standard SMD assembly machines. Typical Applications Radiosondes Weather observation Very short response time High sensitivity and outstanding linearity Reproducible temperature dependence Technical Data Nominal capacitance C0 (at 30 °C / Sensitivity Working range Humidity Temperature Linearity error (0...98 %RH) Hysteresis Response time RH t63 Temperature dependence Loss tangent Maximum supply voltage Maximum DC voltage Operating frequency 1) more details for t < -20 °C (68 °F) on request Sensor Characteristic The following linear approximation of the caracteristic over the range 0–98 %RH leads to errors lower than < ±2 %RH. C(RH) = C0 * [1+HC0 * RH] with HC0 = 3420 ± 250 ppm /% RH HC103M2 v1.4 / Modification rights reserved The average capacitance increases over the working range is around 55 pF. relative humidity [% RH] www.ep

For high accuracy requirements, the characteristic is described by the following polynomial: Mounting Instructions_ For shortest response time, in case of mounting onto a printed circuit board (PCB), HC103M2 shall be positioned over an opening to allow enough air circulation around the sensor. For best accuracy it is important to avoid moisture accumulation such as at the edge of the PCB by selecting appropriate board material or gold-plating the edge of the opening. Please refer to the HC103M2 Handling Instructions at www.epluse.com/hc103m2. HC103M2 is an SMD (surface mounted device) sensor,...