Matsushita Electric Industrial Co., Ltd.

Panasonic Corporation

Masahiko Sasada

Hiroshi Ando

Hiroki Matsunaga

Jinsaku Kaneda

Akihiro Maejima

Eisaku Maeda

Masashi Inao

Hiroki Kinugawa

Nobuo Taketani

Masahiro Takeshima

Minoru Miyata

Hiroshi Moribe

Yutaka Otani

The collector, emitter, and base of a bipolar transistor circuit are connected to a high side power supply terminal, the drain of a level shift transistor, and a floating power supply terminal, respectively. When a high side output transistor is on, the floating power supply terminal is at the potential of a high potential power supply terminal. The high side power supply terminal is at a potential higher than the potential of the floating power supply terminal by a constant voltage. Turning the level shift transistor on, its drain potential drops below the potential of the floating power supply terminal; The base current flows through the bipolar transistor circuit and the drain potential of the level shift transistor is clamped near the potential of the floating power supply terminal; The bipolar transistor circuit is turned on and its collector current supplies the drain current of the level shift transistor.

Sustain driver, sustain control system, and display device

The present invention relates to a layout of a multi-channel semiconductor integrated circuit and provides a layout of a semiconductor integrated circuit having ternary circuits in order to increase a degree of integration in the semiconductor integrated circuit and stabilize output characteristics. A ternary circuit is formed by arranging a second high-side transistor, a diode, a second level shift circuit on one hand, and a low-side transistor, a first high-side transistor, a first level shift circuit, and a pre-driver on the other, so that each of cells are arranged in a row and an output bonding pad is placed between the second high-side transistor and the low-side transistor, wherein a cell width of the first level shift circuit, second level shift circuit and pre-driver corresponds to a cell width of the low-side transistor.

Semiconductor integrated circuit device

Sustain driver, sustain control system, and plasma display

In order to reduce a circuit scale such as a brightness adjustment circuit or the number of pins in an IC chip, in the brightness adjustment circuit, a brightness adjusted video signal (internal video signal) output from an analog signal synthesis circuit or a D/A converter is input to one input terminal of a switch and a sample/hold circuit. The sample/hold circuit holds a voltage of a level in accordance with the pedestal level of the internal video signal at a timing in accordance with a sampling pulse in synchronization with the internal video signal. A clamp circuit clamps the pedestal level of an external video signal in accordance with a clamp pulse, using the voltage held by the sample/hold circuit as the reference voltage, and input it to the other input terminal. The output terminal of the switch is connected to an amplifier.

Pedestal level control circuit and method for controlling pedestal level

The automatic cut-off system includes a video data processing circuit, a cut-off control circuit, a drive circuit, and a level control section. The video data processing circuit adds a cut-off reference pulse having a predetermined level to primary-color signals of red (R), green (G) and blue (B) at different timings within a single vertical blanking interval, and outputs latch timing signals respectively indicating the timings. The cut-off control circuit shifts a level of each primary-color signal having the cut-off reference pulse added thereto based on a corresponding cut-off control signal. The drive circuit drives each cathode of a CRT (cathode-ray tube) based on a corresponding one of the shifted primary-color signals, and outputs a voltage corresponding to each cathode current as a common feedback signal. The level control section latches the feedback signal in response to each latch timing signal, and outputs the cut-off control signal of one of the primary-color signals.

Automatic cut-off system

The object of the present invention is to easily compensate automatic brightness limiting performance and automatic contrast limiting performance even if a picture is displayed with a different aspect ratio and to prevent deterioration of picture quality such as gradation and sharpness. A picture display apparatus includes (1) an automatic brightness limiter (ABL) circuit including a comparison circuit for varying an EHT compensation starting point, an ABL gain control circuit for varying a slope of the EHT characteristic versus the APL, an ABL comparison voltage generator, a DAC for adjusting an ABL compensation starting point and a DAC for adjusting an ABL gain and (2) an automatic contrast limiter (ACL) circuit including another comparison circuit for varying an EHT compensation starting point, an ACL gain control circuit for varying a slope of the EHT characteristic versus the APL, an ACL comparison voltage generator, a DAC for adjusting an ACL compensation starting point and a DAC for adjusting an ACL gain.

Automatic brightness limiter automatic control circuit, contrast limiter

Control circuits for the cut-off and drive control of video equipment. A first control device includes a cut-off control circuit and drive control circuit for use in conventional modes. A second control device includes a cut-off control circuit for mode switching and a drive control circuit for mode switching, independent of the first control device. The cut-off and drive adjustments made for every mode switching operation are unnecessary, and the mode switching based on off set data is possible.

Growing community of inventors

Kyoto, Japan

Masahiko Sasada