TDA8501T/N1,118 NXP Semiconductors, TDA8501T/N1,118 Datasheet - Page 9

• Manufacturer Part Number: TDA8501T/N1,118
• Manufacturer: NXP Semiconductors

Specifications of TDA8501T/N1,118

• Lead Free Status / RoHS Status: Compliant

Philips Semiconductors
April 1993
PAL/NTSC encoder
(1) frequency response.
(2) group delay.
Fig.8
Fig.7
Band pass filter nominal frequency/group
delay response (NTSC mode).
Band pass filter nominal frequency
response (NTSC mode).
9
Y +SYNC, CVBS
The Y signal from the matrix, or the Y signal from pin 5,
(selected via the switch) is added with the composite sync
signal of the sync separator (dependent on pin 17
conditioning). The output of the adder, nominal 1 V
(peak-to-peak), is connected to pin 22 (see Fig.1). Pin 22
is connected to an external delay line.
The delay line is necessary for correct timing of the
Y + SYNC signal with the chrominance signal. The output
resistor of the delay line is connected to V
output of the external delay line is connected to (input)
pin 20.
The Y +SYNC (delayed) input signal at pin 20 is amplified
via a buffer to a level of 2 V (peak-to-peak) nominal and
connected to pin 19 (Y + SYNC output).
The Y
connected via an internal resistor of 2 k to the input of the
CVBS adder stage. After the internal resistor of 2 k , and
before the input of the CVBS adder, an external notch filter
can be connected via pin 18.
The chrominance output of the bandpass filter is added
with Y +SYNC signal via the CVBS adder. The CVBS
(combined video and blanking signal) output of the adder
is connected to pin 16 with a nominal amplitude of 2 V
(peak-to-peak).
The chrominance output of the bandpass filter is amplified
via a buffer and connected to pin 14. The chrominance
amplitude corresponds with the value of Y + SYNC signal
output at pin 19. Together both outputs give the
Y +C (SVHS) signals.
B
PAL mode: Fig.9 illustrates the nominal Y + SYNC signal
at pin 22, the difference between black and blanking level
is 0 mV.
NTSC mode: Fig.10 illustrates the nominal Y + SYNC
signal at pin 22, the difference between black and blanking
level is 53 mV.
Because of the difference between the black and blanking
level in the NTSC mode, there are two options for NTSC.
LACK AND
SYNC (delayed) input signal at pin 20 is also
B
LANKING LEVELS IN
AND
C
HROMINANCE OUTPUTS
PAL
Preliminary specification
AND
NTSC
TDA8501
REF
(pin 13). The
MODES