Power efficient ‘sensor on a chip’ simplifies relative humidity sensingEDN Network, December 9, 2013
Silicon Labs has introduced a family of relative humidity (RH) and temperature sensors that simplify RH sensing designs while claiming provide industry-leading power efficiency and ease of use. Silicon Labs’ second-generation RH sensing solution, the Si701x/2x sensors combine a standard CMOS mixed-signal IC with a proven technique of measuring humidity using a polymer dielectric film. The new family enables accurate RH sensing for home automation, HVAC, refrigeration, healthcare, remote monitoring, automotive and industrial equipment.
The Si701x/2x sensor family provides an alternative to legacy RH sensing approaches, which use discrete resistive or capacitive RH sensing elements along with analog circuits for temperature compensation and signal conditioning. These discrete solutions typically require a large bill of materials and PCB area and suffer from lower reliability and risk of contamination. Customers must also perform RH/temperature calibration during PCB assembly, and discrete solutions are not compatible with surface-mount technology (SMT) manufacturing. RH sensor module suppliers have attempted to solve these manufacturing challenges, but they do so at a higher system cost and without improving reliability or risk of contamination.