Hitachi, Ltd. (TSE: 6501) today announced the HD66752 LCD controller/driver for four-
level grayscale graphics display*1 LCD controller/driver, providing single-chip drive for large
display screen size of 168 x 132 dots, for LCD displays in mobile communication products
such as digital portable phones equipped with a simple browser. Sample shipments will
begin in September 1999 in Japan.
The HD66752 provides four-level grayscale drive of monochrome LCD panels of up to 168 x
132 dots (either wide or tall format) with a single chip, enabling it to handle information
distribution services, including e-mail and Internet WWW contents, on portable
communication terminals.
Digital portable phones are becoming widely used not only as voice terminals, but also as data
communication terminals handling information distribution services such as e-mail and WWW
contents. There is consequently a need for the small LCD panels on these devices to be able
to handle graphic display with grayscales, such as GIF*2, in addition to conventional text-
based displays such as phone numbers and kanji messages. Achieving this capability also
requires a larger screen size.
Hitachi has previously released the HD66741 (128 x 80-dot monochrome display) and
HD66750/751 (128 x 128-dot four-level grayscale display) for the LCD displays on mobile
communication terminals. The lineup is now being extended with the release of the
HD66752 (168 x 132-dot four-level grayscale display), incorporating power supply circuit
-a 7x step-up circuit to achieve a low system power supply voltage- on a single chip.
In case of using a 12 x 12-dot kanji font, the new HD66752 can display up to 154 characters
(14 lines x 11 characters), and also allows screen rotation through 90degrees for an 11 lines x 14
characters display, enabling it to easily handle information distribution services such as e-mail
and WWW contents.
In addition, the four-level grayscale display capability enables a wide variety of graphic
displays to be implemented, and bit operation functions*3 are also provided for smooth
processing of large size of data to support larger screen sizes and grayscale data, making it
possible to greatly reduce the graphics processing load by the microcomputer software.
Larger screen sizes generally need a higher LCD drive voltage and mean a lower display
quality, and increased current dissipation. but the HD66752 cope with below functions.
It is necessary minimum 15V for the LCD drive voltage in case of 168 x132-dot display size.
The HD66752 incorporate the on-chip step-up circuit can generate an LCD drive voltage up
to seven times that of the system power supply voltage, enabling an LCD drive voltage of
approximately 15.4 V to be attained from a 2.2 V power supply.
The LCD drive voltage generation op-amp and step-up circuit drive current can be controlled
by software, allowing current dissipation to be minimized while maintaining display quality.
The drive method used is the C-pattern LCD drive method used in large LCD display systems.
With this method, alternating drive is performed in units of several LCD lines, and the
alternation frequencies of the illuminated and non-illuminated parts of the LCD display are
made uniform, reducing the crosstalk noise due to contrast fluctuations associated with
alternation frequency deviation.
To reduce current dissipation, a partial display function is provided that enables only a part of
the screen display area to be driven. The upper and lower display areas can be driven
independently, enabling display to be performed with a lower LCD drive duty*4.
For example, when displaying five lines for icons at the top of the screen and 19 lines for
message in the center, both displays can be driven at a duty of 1/24.
Supported mounting methods are COF*5 mounting, in which the device is mounted face-
down on a flexible film substrate, and TCP*6 mounting, in which the device is connected
directly to the LCD glass.
Hitachi plans to extend the product lineup in the future with the development of models
capable of handling even larger screen sizes.
Notes: 1. Four-level grayscale graphics display: Bit-mapped display RAM is incorporated,
and graphics are implemented by controlling four levels independently for each dot.
2. GIF (Graphics Interchange Format): A graphical data format frequently used for
WWW contents on the Internet.
3. Bit operation functions: Data processing functions that perform data rewriting and
operations in display RAM for individual display dots.
4. LCD drive duty: Ratio of the drive time for a single line on an LCD screen to the
time for one frame of which the line is a part.
5. COF (Chip On Film): A mounting method in which a chip with a gold bump is
directly mounted face-down on a flexible film substrate.
6. TCP (Tape Carrier Package): A package in which the chip is mounted on a thin-
film tape. Ultra-thin type mounting is possible.
< Typical Applications >
Digital cellular phones (PDC, GSM, CDMA, etc.) with built-in browser
Message pagers, two-way pagers
Small PDAs, handheld GPS terminals, handheld POS terminals, etc.
< Prices in Japan > (For Reference Only)
Product Code Shipment Form Sample Price (Yen)
HCD66752BP Die with gold bump 800
HD66752TB0 Bending TCP 1,050
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