US Patent 7561027 Sensing device

A sensing device is provided. The sensing device includes two or more sensors for sensing one or more physical properties. A first sensor draws a first electrical signal, and similarly, a second sensor draws a second electrical signal. The first and second electrical signals correspond to values of the physical properties sensed by the respective first and second sensors. The sensing device further includes an electrical circuit connected to the first and second sensors. The electrical circuit draws a third electrical signal. The electrical circuit is configured such that the total electrical signal drawn by the sensing device is proportional to either the first or the second electrical signal, whichever has a higher value.