Sony Corporation

Yasuharu Baba

Masashi Takeda

Hiroshi Nakazawa

Takeo Sekino

Masayuki Miyake

An oscillator which includes a DC voltage source, a differential amplifier having a hysteresis characteristics, a current source circuit producing a predetermined constant current, a current sink circuit flowing therein substantially one half of the predetermined constant current, and first and second current switching circuits controlled by the output of the hysteresis amplifier to charge/discharge a capacitor by the current from current source/sink circuits, thereby to produce an output pulse signal.

Oscillator having capacitor charging and discharging controlled by

A sawtooth wave oscillator is disclosed which includes a series connection consisting of a charging circuit and a first capacitor, a voltage dependent capacitor connected in parallel to the first capacitor, and a discharging circuit connected in parallel to the first capacitor, whereby a sawtooth wave which has good linearity can be generated with a simple circuit construction.

Sawtooth wave oscillator

A flip-flop circuit is disclosed which has a first semiconductor region of a first conductivity type, injector and base regions of a second conductivity type in the first region, and collector region of the first conductivity type in the base region. In this case, the first, base and collector regions constitute a gate transistor, two of the gate transistors constitute a flip-flop circuit, and each of the transistors has a predetermined distance relation among the injector and collector regions and base contacts in such a manner that the inherent difference of ON and OFF speeds between the transistors causes the flip-flop circuit to operate without causing unnecessary delay.

Flip-flop circuit

A switching regulator includes a DC voltage source having a pair of DC output terminals, a switching transformer having a magnetic core, first and second primary windings and a secondary winding, a first switching transistor connected in series between the pair of DC output terminals through the first primary winding, a second switching transistor connected in series between the pair of DC output terminals through the first and second primary windings, and a rectifier circuit connected across the secondary winding. A pulse width modulator is provided to produce a PWM (pulse width modulated) control signal the duty of which is proportional to the voltage of the rectifier circuit, and the PWM control signal is selectively supplied to one of the first and second switching transistors in response to the low or high circumstance of a load connected to the rectifier circuit. Further, a control circuit is provided so as not to excessively drive one of the first and second switching transistors during the switching operation thereof.

Growing community of inventors

Atsugi, Japan

Yasuharu Baba