Abstract: A wakeup process of a living body tactile sensor and a wearing determination unit is performed when an accelerometer detects an acceleration. Accordingly, the living body tactile sensor and the wearing determination unit are in a sleep mode while the accelerometer detects no acceleration. When the wearing determination unit determines a non-wearing state, the wearing determination unit performs a sleep process to switch itself from a wakeup mode to the sleep mode.

Abstract: The screen of a liquid crystal panel is divided into two portions. In the divided screens (upper screen and lower screen), the corresponding common electrodes (each for one divided screen) are simultaneously driven. The driving signal (common signal C1) of the upper screen and the driving signal (common signal C2) of the lower screen change in one cycle of four frame periods. More specifically, in the above-mentioned cycle, the common signal C1 changes in a pattern (1→1→1→−1), and the common signal C2 changes in a pattern (1→−1→1→1) in synchronization with each other. Accordingly, upon comparison of the common signals C1 and C2, it appears that the signal having the same waveform is applied to the common electrodes while being out of phase with each other. Thus, a difference of the drive frequency between the upper screen and the lower screen is eliminated.

Abstract: There is provided a small size and low price driving voltage generator (of a liquid crystal display unit) which can easily adjust output voltages. In this driving voltage generator, a DC-DC converter raises an input voltage (5 [V]) and produces voltages VH and VL. Resistors divide a voltage difference between the voltages VH and VL with resistors. Operational amplifiers output through current amplification each voltage divided by resistance. In the present invention, the external size can be reduced because only two output terminals are required for the DC-DC converter. In addition, manufacturing cost can be lowered because only two output terminals are required for the DC-DC converter. Moreover, since the resistors R1 to R6 are provided in the outside of the DC-DC converter (hybrid IC), these resistors can be exchanged easily. Therefore, the voltages V HCOM, V HSEG, V M, V LSEG, V LCOM can be adjusted easily.