TDA4780 Datasheet, PDF (19/44 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
RGB input 2 (R₂: pin 2, G₂: pin 3, B₂: pin 4; capacitively coupled to a low-ohmic source;
recommendation: maximum 600 Ω); note 1
V_{2, 3, 4(p-p)}
R_{2, 3, 4}
V_{2, 3, 4}
I_{2, 3, 4}
input signal (peak-to-peak value)
AC input resistance
internal bias during clamping
DC input current between clamping
pulses
−
0.7 −
V
10.0 −
−
MΩ
−
5.1 −
V
−
−
0.1 µA
I_{2, 3, 4(max)(clamp)} maximum input current during clamping
100 180 260 µA
Fast signal switches and blanking (fast signal switch 1 (pin 13); Y, CD / R₁, G₁, B₁; control bits FSDIS1,
FSON1)
V₁₃
voltage to select Y and CD
V₁₃
voltage range to select R₁, G₁ and B₁
R₁₃
internal resistor to ground
−
0
0.4 V
0.9 1.0 5.5 V
3.3 3.8 4.8 kΩ
CROSSTALK (SEE TABLE 5)
t_s − t_i
difference between transit times for
signal switching and signal insertion
−
−
10 ns
Fast signal switch 2 (pin 1; Y, CD or R₁, G₁, B₁ / R₂, G₂, B₂; control bits FSDIS2, FSON2)
V₁
voltage to select Y and CD / R₁, G₁ and
B₁
V₁
voltage range to select R₂, G₂ and B₂
V₁
required minimal voltage to switch off the
ADBL measurement
−
0
0.4 V
0.9 1.0 5.5 V
−
0.87 1.0 V
R₁
internal resistor to ground
R₁ > R₁₃
2.8 4.2 6.0 kΩ
CROSSTALK (SEE TABLE 5)
t_s − t_i
difference between transit times for
signal switching and signal insertion
−
−
10 ns
Adjust stages (adaptive black, gamma, contrast, saturation, brightness and white point adjust, blue stretch)
ADAPTIVE BLACK (DETECTORS INACTIVE STATUS DUE TO ACTION OF FAST SWITCH 2 (PIN 1); see Table 4, Fig.9 and note 2)
I_18(dch)
discharge current of peak dark storage outside active
−1.0 0.0
capacitor
measurement window
+1.0 µA
inside active
1.5 2.5 3.5 µA
measurement window
I_18(ch)
charge current of peak dark storage
capacitor
−360 −300 −250 µA
d_bl(max)
maximum level shift: ∆ black level in
percent of nominal signal amplitude
10 13 16 %
d_bl(nom)
difference between nominal black and
adaptive black in percent of nominal
signal amplitude
−3 0
+3 %
t_dibb
detectors inactive time before blanking
t_diab
detectors inactive time after blanking
2.3 3.1 4.0 µs
2.3 2.5 3.4 µs
1997 Feb 06
19