March 16, 1998
Hitachi Releases the Industry's First Graphics LCD Controller/driver with a Character Generator ROM for JIS Level 1 and 2 Kanji Characters- Microprocessor font processing time reduced to 1/60 that of previous Hitachi products, and High-performance, compact systems made possible -The controller/driver has a large capacity built-in font ROM which eliminates the necessity of conventional external kanji character generator ROM and drastically reduces kanji font software processing time of the microprocessor to about 1/60 that of previous Hitachi products. The display ROM also boasts full-graphics display functionality that can be used for games and other purposes. Small LCD panels are used widely in communication equipment such as cellular telephones, Personal Handyphone System (PHS) telephones, pagers, cordless phones, and business telephones. To make the most of ever-progressing cellular and PHS phones, recently there is strong demand for the ability to display kanji characters, as well as Japanese phonetics, the English alphabet, and numerals as in current systems. Digital cellular systems have also been launched and are expanding in other Asian countries, such as the CDMA*1 and PCS*2 in Korea, and GSM*3 in Chinese-speaking countries. As the number of users increases, demand is rising for a switch to products that can display hangul and Chinese characters. In the future, for more diversified communication services and higher added value, graphic display function for games and maps is desired, as well as text-oriented function for a kanji- written address book and so on. Previously, displaying kanji, hangul, or Chinese characters required an LCD driver chip with bit map RAM in combination with a character generator ROM chip. Every time the font pattern was loaded from the ROM to the RAM-incorporated LCD driver, extra processing loads were added as an overhead to the CPU, whose main task is digital communication processing. This posed a real problem in regarding design of the next generation of digital cellular phones with high functionality, high performance, and low power consumption. Hitachi's new product satisfies these market demands and the meets for greater display data capacity, by its high capacity ROM, high functionality, and low power consumption based on the concept of HD 66730 and HD66731, the LCD controller-drivers with the JIS level 1 kanji character generator ROM that are already in volume production. This product integrates the character generator ROM that stores the complex dot patterns of kanji, hangul, or Chinese characters, and the bit map RAM required for full- graphic display, into a single chip. Compared with a Hitachi's previous LCD driver that uses built-in RAM and external kanji/hangul/Chinese font ROM, the new product takes up only a half installation space, making a compact LCD system. The system displays kanji, hangul, or Chinese characters according to simple 2-byte standard JIS character codes sent from the CPU, thereby dramatically reducing the CPU's software processing burden during front loading to about 1/60 of that in previous Hitachi products. The additional incorporation of a power op-amp for low- power consumption LCD drive reduced the current consumed for driving the LCD to about 1/3 that of previous Hitachi products. Up to 40 full-width characters can be displayed in the 10 characters x 4 lines display area. By use of the half-width font for alphanumeric characters for phone numbers, etc., more than 40 characters can be displayed on a screen of limited area. The character generator contains JIS level 1 and level 2 kanji characters and about 8,000 non-kanji characters in the 11x12-dot full- width font, plus 256 characters in the 6-12-dot font. Up to 40 full- width user-defined characters can also be used. Full-graphics display at 120x52 dots is available. In addition to the kanji and graphics display, up to 200 marks can be displayed by the segment display function. Various types of display are possible, in combination with the blink function if preferred, for battery alarm, etc. The superimpose display function that displays kanji text and bitmap full graphics images at the same time adds to display versatility. The vertical smooth scroll function that moves the screen image up and down in one-dot increments enables massive information display on a tiny LCD panel. Smooth scrolling was previously available only by the bit map display system which controlled the on-off state of individual dots separately. The new product scrolls easily and smoothly, with minimal burden the CPU. The key scan function controls 4x8 (32) key matrices. This makes it possible to control the LCD panel and the keyboard by a single chip, contributing to system miniaturization and cost saving. The fourfold booster circuit generates a maximum of 12 volts of LCD drive voltage at a power voltage of 3 volts, realizing 3-V single power operation. The LCD drive duty, LCD drive bias, and the output ratio from the booster circuit are all controllable by software. By this, power consumption can be suppressed by reducing the LCD drive bias and the LCD drive voltage when only a part of the LCD screen needs to be driven in system standby state. When nothing needs to be displayed at all, the standby mode function and the booster circuit stop function significantly save the total power consumption of the set. This HD66732 is available both in a bend tape carrier package (TCP) that can be mounted by bending the border between the chip and the LCD glass on TCP tape and as a gold bump chip product that allows chip on glass (COG) mounting*5 and chip on film (COF) mounting*6. The bend TCP product has the advantage that it can be placed on the LCD glass directly without using the heat seal. Note:
Application Products
Prices in Japan *For Reference
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