TDA4671 Datasheet, PDF (2/16 Pages) NXP Semiconductors – Picture Signal Improvement PSI circuit

Philips Semiconductors
Picture Signal Improvement (PSI) circuit
Product specification
TDA4671
FEATURES
• Luminance signal delay from 20 to 1100 ns (minimum
step 45 ns)
• Luminance signal peaking with symmetrical overshoots
selectable
• Selectable 2.6 or 5 MHz peaking centre frequency and
degree of peaking (−3, 0, +3 and +6 dB)
• Selectable noise reduction by coring
• Handles negative as well as positive colour-difference
signals
• Selectable Colour Transient Improvement (CTI) to
decrease the colour-difference signal transient times to
those of the high frequency luminance signals
• Selectable 5 or 12 V sandcastle input voltage
• All controls selected via the I²C-bus
• Timing pulse generation for clamping and delay time
control synchronized by sandcastle pulse
• Automatic luminance signal delay correction using a
control loop
• Luminance and colour-difference input signal clamping
with coupling capacitor
• 4.5 to 8.8 V supply voltage range
• Minimum of external components.
GENERAL DESCRIPTION
The TDA4671 delays the luminance signal and improves
colour-difference signal transients. The luminance signal
can also be improved by peaking and noise reduction
(coring).
QUICK REFERENCE DATA
SYMBOL
V_P
I_P(tot)
t_d(Y)
V_i(VBS)(p-p)
V_i(CD)(p-p)
G_Y
G_CD
T_amb
PARAMETER
MIN.
supply voltage (pins 1 and 5)
4.5
total supply current
31
Y signal delay time
20
composite Y input signal (peak-to-peak value, −
pin 16)
colour-difference input signal
(peak-to-peak value)
±(R − Y) on pin 3
−
±(R − Y) on pin 7
−
gain of Y channel
−
gain of colour-difference channel
−
operating ambient temperature
0
TYP.
5
41
−
450
1.05
1.33
−1
0
−
MAX.
8.8
52
1 130
640
1.48
1.88
−
−
70
UNIT
V
mA
ns
mV
V
V
dB
dB
°C
ORDERING INFORMATION
TYPE
NUMBER
TDA4671
NAME
DIP18
PACKAGE
DESCRIPTION
plastic dual in-line package; 18 leads (300 mil)
VERSION
SOT102-1
1996 Dec 11
2