Fujitsu Corporation

Yukio Murayama

Hisamitsu Takagi

Seiji Goto

Masashi Tomura

Akihide Nishiyama

Hideharu Suzuki

Takao Hara

Kazuaki Tsunoda

A current measuring circuit for measuring discharging current and charging current of a battery, which is selectively connected to a load and a charger. The current measuring circuit comprises a resistor connected in series with the battery having a sufficiently low resistance value as not to substantially restrain the output current from the battery and a differential amplifier for amplifying a potential difference between both ends of the resistor. By providing a switch for short-circuiting one input terminal and the other input terminal of the differential amplifier, an offset/drift voltage of the differential amplifier can be obtained. This offset/drift voltage is used for correcting the output voltage from the differential amplifier at the time of current measurement and, thereby, the discharging current and charging current of the battery can be measured accurately.

Circuit for measuring discharging and charging current of a battery

A compact portable telephone, in which a sufficient distance between the receiving portion and the voice inlet portion can be secured when the telephone is used. A flexible pipe member formed of metallic or dielectric material is slidably or swingably attached to the main body of the telephone or has its base fixedly attached to the main body. The flexible pipe member is provided at its end with a microphone. When the flexible pipe member is formed of metallic material, the flexible pipe member is used as an antenna. When the flexible pipe member is formed of dielectric material, at least one of a pair of cords connected to the microphone is utilized as an antenna.

Portable telephone having a pipe member which supports a microphone

A signal detection circuit for determining synchronism and asynchronism in a phase synchronization circuit having a loop consisting of a first phase detector, a loop filter and a voltage controlled oscillator, has a second phase detector for input signals of the phase synchronization circuit and output signals of the voltage controlled oscillator. The output of the second phase detector is supplied to a low pass filter and a level judgment circuit. The level judgment circuit includes a Schmitt trigger circuit with two threshold levels due to hysteresis effect to reduce misjudgments when the input signals are low signal to noise signals.

Signal detection circuit

Growing community of inventors

Kawasaki, Japan

Yukio Murayama