A liquid crystal device includes a pair of substrates, a liquid crystal layer provided between the substrates, and a plurality of sub-pixels each having a transmissive display region and a reflective display region. LEDs 8 are arranged below the key tops 7. By obtaining the installation site address and the identifiable information, it is possible to associate the installation site address to the factory automation product based on the identifiable information. The second current mirror is further configured to provide a portion of the first current to the output of the current circuit as the output current and to receive another portion of the first current and mirror the same as the second portion of the reference current.