TDA4780 Datasheet, PDF (21/44 Pages) NXP Semiconductors – RGB video processor with automatic cut-off control and gamma adjust

Philips Semiconductors
RGB video processor with automatic
cut-off control and gamma adjust
Preliminary specification
TDA4780
SYMBOL
PARAMETER
CONDITIONS
MIN. TYP. MAX. UNIT
DIFFERENCES OF BLACK LEVEL STEPS (DIFFERENCES FROM CHANNEL TO CHANNEL OF THE RATIO OF THE DIFFERENCE
(BLACK LEVEL CUT-OFF MEASUREMENT LEVEL) TO ACTUAL NOMINAL SIGNAL AMPLITUDE (V_NOM24, V_NOM22, V_NOM20) OVER THE
WHOLE CONTRAST, BRIGHTNESS AND SATURATION RANGE, SWITCHING MATRIX OR SWITCHING FAST SWITCHES, GAMMA = 1,
BLST = 0, ADBL = 0)
∆V/V_nom
static deviation
note 6; ripple on pin 5 −1.0 −
during clamping ≤1 mV;
note 7
+1.0 %
at nominal saturation −0.5 −
+0.5 %
RGB outputs (output for positive RGB signals (R: pin 24, G: pin 2, B: pin 20); following data without external
load)
R_{24, 22, 20}
I_{24, 22, 20(max)}
V_{24, 22, 20(min)}
V_{24, 22, 20(max)}
V_{24, 22, 20(max)(p-p)}
differential output resistance
maximum output current
minimum output voltage
maximum output voltage
maximum signal amplitude (black-white)
due to internal limits
(peak-to-peak value)
note 8
R_L ≥ 2 kΩ
−
25 30 Ω
4.0 5.0 −
mA
−
−
0.8 V
6.3 7.0 −
V
3.3 −
−
V
V_{24, 22, 20(max)(p-p)} nominal signal amplitude (black-white; at nominal white adjust, 1.7 2.0 2.3 V
peak-to-peak value)
contrast and saturation
setting; gamma = 1;
nominal input signals
V_{24, 22, 20}
V_{24, 22, 20}
cut-off measurement level
recommended cut-off measurement
level
note 8
1.0 −
5.0 V
−
3.0 −
V
OUTPUT CLAMPING (RGB)
V_{20, 22, 24}
clamp voltage black level
WHITE POTENTIOMETERS
∆G_v(inc)(max)
maximum increase of AC gain
∆G_v(dec)(max)
maximum decrease of AC gain
control bit BCOF = 1 2.3 2.5 2.7 V
I²C-bus data 3FH;
relative to nominal
setting; note 9
I²C-bus data 00H;
relative to nominal
setting; note 9
40 50 60 %
40 50 60 %
1997 Feb 06
21