Semiconductor Group

10

RGB, Y, U, V Outputs

A digital RGB matrix converts the Y, U, V data in R, G, B data.

The equation of the implemented RGB Matrix are:

R = Y + 0.75 V

G = Y – 0.375 V – 0.1875 U

B = Y + U

For a signal with 100 % white and 75 % color saturation the amplitudes of the analog input signals

have to be set according the following relation:

Y / U / V = 0.72 / 0.95 / 1

By means of an internal switch at the output of the RGB matrix it is possible to by-pass the matrix

with the digital data for Y, U and V and feed them directly into the D/A converters. During this

operation mode the chrominance data U and V will be inverted.

D/A Conversion

SDA 9188-3X includes three 6-bits D/A converters. Each D/A converter delivers a current through

an external resistor that is to be connected between OUT1-OUT3 and

V

determines the output voltages (see application circuit). The assignment of outputs OUT1-OUT3

Register 4.

The tolerances of the output voltages can be reduced significantly if the resistor at

V

by means of a constant current source.

Table 5

Assignment of Output Signals to OUT1-OUT3

Borderframe

The width of the border frame can be adjusted in two steps, the intensity of the frame can be set in

Output

RGB

YUV

OUT1

R

– V

OUT2

G

Y

OUT3

B

– U

SDA 9188-3X