TDA8310 Datasheet, PDF (19/24 Pages) NXP Semiconductors – PAL/NTSC colour processor for PIP applications

Philips Semiconductors
PAL/NTSC colour processor for
PIP applications
Preliminary specification
TDA8310
24. The reference signal for the TDA8395 is available only when the crystal oscillator is operating at a frequency of
4.43 MHz. When a SECAM signal is identified this signal is only available during the vertical retrace period thus
avoiding crosstalk with the incoming SECAM signal during scan.
25. The identified colour standard can be read from the IC in two ways:
a) From the voltage level of pin 4. The voltage during the demodulation of the various standards is given in the last
three parameters of this section.
b) From the pins 23 to 26 when pin 27 is in the “read” mode.
When pin 27 is in the “write” mode the colour decoder can be forced to one of the colour standards. The levels for
the various standards are given in Tables 2, 3 and 4.
26. When one or more pins have to be connected to the positive supply line the total current must be limited to 40 µA.
This can be achieved by connecting these pins together and connecting them to a positive supply line via a 100 kΩ
resistor. When separate resistors are used a resistor with a higher value must be used so that the total current is
limited to the required level.
27. The output of pin 4 is designed similar to the sandcastle output. The output is pulled down during PAL and pulled up
during SECAM. During NTSC the pin is floating so that the output level is determined by the load.
28. The control possibilities of the RGB switch via pins 13 and 52 are shown in Table 5.
29. This output signal value is obtained when the CVBS or Y input signal at pins 17 and/or 20 has an amplitude of 0.7 V
(black-to-white value).
30. The output buffer consists of a combination of a PMOS and an NMOS. The maximum output impedance in the low
state can be calculated by dividing the maximum output voltage (for this parameter 0.9 V) by the specified current.
For the high state this resistance can be calculated by dividing the difference between the maximum and minimum
output voltage by the specified current. The output impedance is independent of the value of the output current.
31. These output signal values are obtained for a colour bar input signal with 75% saturation.
Table 1 Output current of phase detector
CURRENT PHASE
DETECTOR
DURING
SCAN
(µA)
Weak signal and
30
synchronized
Strong signal and 180
synchronized
Not synchronized 180
VERTICAL
RETRACE
(µA)
30
270
270
GATED
YES/NO
YES
(5.7 µs)
NO
NO
Table 2 Read/write pin input (pin 27)
MODE
Decoder automatic
Forced decoder mode
LEVEL
LOW
HIGH
Table 3 Colour system logic (pins 25 and 26)
PIN 25
LOW
LOW
HIGH
HIGH
PIN 26
LOW
HIGH
LOW
HIGH
STANDARD
auto/no colour
PAL
NTSC
SECAM
Table 4 Crystal logic (pins 23 and 24)
PIN 23
LOW
LOW
HIGH
HIGH
PIN 24
LOW
HIGH
LOW
HIGH
SELECTED CRYSTAL
(MHz)
4.43
3.579 (NTSC)
3.575 (PAL-M)
3.582 (PAL-N)
Table 5 Control logic RGB switch (pins 13 and 52)
PIN 13
LOW
LOW
HIGH
HIGH
PIN 52
LOW
HIGH
LOW
HIGH
RGB
OUTPUT
black
RGB 2
RGB 1
RGB 2
FAST
BLANKING
OUTPUT
LOW
HIGH
HIGH
HIGH
February 1995
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