Hitachi, Ltd.

Renesas Technology Corp.

Renesas Electronics Corporation

Other

Hitachi Device Engineering Co., Ltd.

Hitachi Engineering Co., Ltd.

Synaptics Display Devices Gk

Yoshikazu Yokota

Kimihiko Sugiyama

Kazuhisa Higuchi

Kunihiko Tani

Yasuyuki Kudo

Gorou Sakamaki

Atsuhiro Higa

Takashi Yoneoka

Katsuhiko Yamamoto

Hiroshi Takeda

Tsutomu Furuhashi

Naoki Miyamoto

Kazunari Kurokawa

Toshio Mizuno

Kazuo Ookado

Toshimitsu Matsudo

Takayuki Nakaji

Takatoshi Uchida

Kazuya Endo

Koyo Katsura

Shigeru Matsuo

Jun Sato

Takashi Sone

Hideki Yamazaki

Masahiko Kikuchi

Hiroshi Kurihara

Satoru Tsunekawa

Goro Sakamaki

Shigeru Ohta

Kei Tanabe

Takashi Ohyama

Yasuhito Kurokawa

Atsushiro Higa

A display control device and technique for controlling displays on a display unit, in which a plurality of display segments are two-dimensionally arranged (e.g. a dot matrix type display unit), is provided. The technique is effectively applicable to a write data latch circuit of a memory for storing display data in the display control device, such as, for example, a liquid crystal display control device, a mobile electronic apparatus, etc. A display drive control technique for controlling a moving picture display mode of a display device is also provided. The display drive control circuit controls a picture display mode of a display device for displaying still pictures and moving pictures to a liquid crystal display device, such as, for example, a dot matrix type display devices, an organic EL display device, etc.

Display control device and mobile electronic apparatus

In conventional liquid crystal display controllers, the display is reduced in the stand-by state but the liquid crystal display duty is not changed, i.e., even the common electrodes of the rows that are not producing display are scanned, and the consumption of electric power is not decreased to a sufficient degree in the stand-by state. A liquid crystal display controller includes a drive duty selection register capable of being rewritten by a microprocessor, and a drive bias selection register. When the display is changed from the whole display on a liquid crystal display panel to a partial display on part of the rows only, the preset values of the drive duty selection register and of the drive bias selection register are changed, so that the display is selectively produced on a portion of the liquid crystal display panel at a low voltage with a low-duty drive.

Liquid crystal display controller and liquid crystal display device

The present invention provides a liquid crystal display controller device and method which provides for a full and/or partial display with good display quality and/or low power consumption based on the scanning period for an active scan line being dependent upon a number of reference clock pulses. Some embodiments of the present invention include one or more of the following features: keeping the frequency substantially constant for different numbers of active scan lines, allowing change of the frequency due to characteristics of the LCD, displaying gradation with near linear effective voltage characteristics, displaying graduation data with lower power, or displaying a partial or full screen in a mobile device, for example, a cell phone.

Liquid crystal display controller

In conventional liquid crystal display controllers such as for portable telephone sets, the display is reduced in the stand-by state but the liquid crystal display duty is not changed, i.e., even the common electrodes of the rows that are not producing display are scanned, and the consumption of electric power is not decreased to a sufficient degree in the stand-by state. A liquid crystal display controller () includes a drive duty selection register () capable of being rewritten by a microprocessor (), and a drive bias selection register (). When the display is changed from the whole display on a liquid crystal display panel () to a partial display on part of the rows only, the preset values of the drive duty selection register and of the drive bias selection register are changed, so that the display is selectively produced on a portion of the liquid crystal display panel at a low voltage with a low-duty drive.

A liquid crystal display device includes a liquid crystal display panel and a semiconductor integrated circuit for driving and controlling the liquid crystal display panel. The number of input/output wires connected to I/O terminals (bonding pads) of the semiconductor integrated circuit is reduced so as to simplify wiring patterns of the I/O wires, whereby degrees of freedom in arranging the I/O wiring patterns are enhanced. The panel has a pair of insulating substrate, and the semiconductor integrated circuit is mounted on one of the paired substrates. The semiconductor integrated circuit has a mode terminal which is fixed to a power supply potential or to a reference potential during operation of the integrated circuit, and power supply dummy terminals connected to the power supply potential or reference potential inside the semiconductor integrated circuit. The wiring patterns formed on the paired insulating substrates connect the mode terminal to the power supply dummy terminals.

Liquid crystal display device, method for fabricating the same, and portable telephone using the same

A liquid crystal display device comprises a liquid crystal display panel and a semiconductor integrated circuit for driving and controlling the liquid crystal display panel. The number of input/output wires connected to I/O terminals (bonding pads) of the semiconductor integrated circuit is reduced so as to simplify wiring patterns of the I/O wires, whereby degrees of freedom in arranging the I/O wiring patterns are enhanced. The panel has a pair of insulating substrate, and the semiconductor integrated circuit is mounted on one of the paired substrates. The semiconductor integrated circuit has a mode terminal which is fixed to a power supply potential or to a reference potential during operation of the integrated circuit, and power supply dummy terminals connected to the power supply potential or reference potential inside the semiconductor integrated circuit. The wiring patterns formed on the paired insulating substrates connect the mode terminal to the power supply dummy terminals.

A display device for displaying display data includes a display panel having pixel sections in a matrix form, a scanning circuit which selects a line of the pixel sections, a generation circuit which generates a plurality of gray-scale voltages based on a reference voltage, and a selection circuit which selects a gray-scale voltage corresponding to the display data from the plurality of gray-scale voltages, and outputs the gray-scale voltage thus selected to a pixel section of the display panel. The generation circuit one of increases and decreases a steady-state current of the generation circuit at a second period within one scanning period of the scanning circuit.

Display device with control of steady-state current of a generation circuit

There is to be provided a liquid crystal drive controller with a built-in power supply circuit wherein latch-up is made difficult to arise even if one amplitude level of the segment line drive voltage is set to the ground potential and the levels of other liquid crystal drive voltages are determined accordingly. A semiconductor integrated circuit with a built-in power supply circuit, wherein a negative voltage generated in a power supply circuit is applied to a substrate or a well region as a bias voltage, is provided with a switch for temporarily applying the ground potential to the substrate or well region to be biased with the negative voltage at the time of starting up the power supply circuit.

Semiconductor integrated circuit with voltage generation circuit, liquid crystal display controller and mobile electric equipment

A matrix type liquid crystal display device has a function of suppressing power consumption without calling for an extra circuit arrangement such as the arrangement of storage capacitance and wiring to storage capacitance and without disposing new external components. A switch is disposed in the liquid crystal display device to temporarily short-circuit both column electrodes and common electrodes sandwiching a liquid crystal between them in synchronism with an alternation timing.

Liquid crystal drive circuit and liquid crystal display device

Growing community of inventors

Kodaira, Japan

Yoshikazu Yokota