Seiko Instruments Inc

Osamu Imagawa

Hiroyuki Watanabe

Koichi Shibata

Toshitaka Fukushima

Shinichiro Miyahara

The portable information apparatus has a battery, a boosting circuit for boosting a voltage of the battery, a battery voltage detector for detecting a voltage level of the battery, an oscillating circuit for generating CPU clock and a counting circuit for counting the interval from the start of the oscillation of the CPU clock to the time when it becomes stable. The apparatus negates the output of the battery voltage detector during the interval counted by the counting circuit so that it can prevent the monitoring of the battery voltage lowering in the time of usual performance from influencing of the battery potential drop due to the transient current at the start of the performance of the boosting circuit and the oscillating circuit.

Portable information apparatus for sensing battery voltage drop

The synchronous serial communication circuit transmits and receives data, which is added flag patterns for recognizing the coil winding direction at the first and last of data block, by the electromagnetic induction system using a pair of coils. So, the circuit provides modulation and demodulation circuits acting at the clock of twice of the transfer speed and a flag check circuit for recognizing the inversion of the coil winding direction by judging a state of the flag patterns included in the received data. The transmitted data is converted into the biphase signal by the modulation circuit and is transmitted by driving the coil using the biphase signal. The signal received by the coil is converted into the received data by the demodulation circuit. When the winding directions of coils does not agree, the flag check circuit recognizes the inversion of the coil winding direction and the received data is inverted by the demodulation circuit.

Growing community of inventors

Tokyo, Japan

Osamu Imagawa