S1D13700F01A100 Epson, S1D13700F01A100 Datasheet - Page 92

• Manufacturer Part Number: S1D13700F01A100
• Description: Display Drivers LCD CONTROLLER
• Manufacturer: Epson

Specifications of S1D13700F01A100

• Operating Temperature (min): -40C
• Operating Temperature (max): 85C
• Operating Temperature Classification: Industrial
• Package Type: TQFP
• Pin Count: 80
• Mounting: Surface Mount
• Operating Supply Voltage (min): 2.7V
• Lead Free Status / Rohs Status: Supplier Unconfirmed

4 L
S1D13705F00A PROGRAMMING NOTES
AND EXAMPLES (X27A-G-002-01)
This section is supplemental to the description of the Look-Up Table architecture found in the
S1D13705 Hardware Functional Specification. Covered here is a review of the LUT registers,
recommendations for the color and gray shade LUT values, and additional programming
considerations for the LUT. Refer to the “S1D13705 Hardware Functional Specification”,
document number X27A-A-001-01 for more detail.
The S1D13705 Look-Up Table consists of 256 indexed red/green/blue entries. Each entry is 4 bits
wide. Two registers, REG[15h] and REG[17h], control access to the LUT.
Each Look-Up Table entry consists of a red, green, and blue component. Each component consisting
of four bits, or sixteen intensity levels. Any Look-Up Table element can be selected from a palette of
4096 (16 16 16) colors.
In color display modes, pixel values are used as an index to an RGB value stored in the Look-Up
Table. In monochrome modes, pixel values still index into the LUT, but only the green component is
used to determine display intensity.
The selected color depth determines how many index positions are used for image display. For
example at one bit-per-pixel (bpp) only index positions 0 and 1 of the Look-Up Table are used. At 4-
bpp the first 16 index positions of the Look-Up Table are used and at 8-bpp all 256 Look-Up Table
index positions are used.
The Look-Up Table mechanism itself consists of an index register and a data register. The index, or
address, register determines which element of the Look-Up Table will be accessed. After setting the
index the LUT may be read or written through the data register. The first data element read or written
is the red component of the entry. Subsequent read/write operations access the green and then the
blue elements of the Look-Up Table.The S1D13705 LUT architecture is designed to provide a high
degree of similarity in operation to a standard VGA RAMDAC. However, there are two
considerations which must be kept in mind.
• The S1D13705 Look-Up Table has four bits (16 levels) of intensity per primary color. The
standard VGA RAMDAC has six bits (64 levels). This four to one difference must be taken into
consideration when converting from a VGA palette to a LUT palette. One suggestion is to divide
the VGA intensity level by four to arrive at the LUT intensity.
However, most applications specify the red, green and blue components as eight bit intensities. To
determine the appropriate S1D13705 Look-Up Table value we recomend using the four most
significant bits.
OOK
-U
P
T
ABLE
(LUT)
EPSON
4: LOOK-UP TABLE (LUT)
2-7