SSD1818A datasheet(21/47 Pages) ETC

21 / 47 page

SSD1818A

Rev 1.2

P 21/47 Mar 2004

Solomon Systech

Reset Circuit

This block includes Power On Reset (POR) circuitry and the hardware reset pin, RES . The POR and

Hardware reset performs the same reset function. Once RES receives a reset pulse, all internal circuitry

will start to initialize. Minimum pulse width the reset sequence is 5 - 10us. Status of the chip after reset is

given by:

Display is turned OFF

Default Display Mode: 104 x 64 + 1 Icon Line

Normal segment and display data column address mapping (Seg0 mapped to Row address 00h)

Read-modify-write mode is OFF

Power control register is set to 000b

Shift register data clear in serial interface

Bias ratio is set to default: 1/9

Static indicator is turned OFF

Display start line is set to GDDRAM column 0

Column address counter is set to 00h

Page address is set to 0

Normal scan direction of the COM outputs

Contrast control register is set to 20h

Test mode is turned OFF

Temperature Coefficient is set to TC0

Note: Please find more explanation in the Applications Note attached at the back of the specification.

Display Data Latch

This block is a series of latches carrying the display signal information. These latches hold the data,

which will be fed to the HV Buffer Cell and Level Selector to output the required voltage level.

64 MUX: 104 + 65 = 169

HV Buffer Cell (Level Shifter)

HV Buffer Cell works as a level shifter, which translates the low voltage output signal to the required

driving voltage. The output is shifted out with reference an internal FRM clock that comes from the

Display Timing Generator. The level selector, which is synchronized with the internal M signal, gives the

voltage levels.

Level Selector

Level Selector is a control of the display synchronization. Display voltage levels can be separated into two

sets and used with different cycles. Synchronization is important since it selects the required LCD voltage

level to the HV Buffer Cell, which in turn outputs the COM or SEG LCD waveform.

SSD1818A Datasheet(PDF) 21 Page - List of Unclassifed Manufacturers