1998 Feb 09

18

Philips Semiconductors

Product specification

Multistandard VIF-PLL with QSS-IF

and dual FM-PLL/AM demodulator

TDA9814T

16. Input level for second IF from an external generator with 50

Ω source impedance. AC-coupled with 10 nF capacitor,

have to be connected to positive supply voltage for minimum IF gain. S/N and THD measurements are taken at 50

µs

de-emphasis. The not tested FM-PLL has to be locked to an unmodulated carrier.

a) Second IF input level 10 mV RMS.

decoder family TDA9840. For handling an FM deviation of more than 53 kHz the AF output signal has to be reduced

18. The leakage current of the decoupling capacitor (2.2

µF) should not exceed 1 µA.

19. In the event of activated auto mute state the second FM-PLL oscillator is switched off, if the input signal at pin 14 is

missing or too weak (see Fig.13). In the event of switching the second FM-PLL oscillator on by the auto mute stage

an increased DC jump is the consequence. Note, that noise at pin 14 disables the mute state (at low SIF input signal),

but this will not lead to false identification of the used stereo decoder family TDA9840.

20. For all S/N measurements the used vision IF modulator has to meet the following specifications:

a) Incidental phase modulation for black-to-white jump less than 0.5 degrees.

b) QSS AF performance, measured with the television-demodulator AMF2 (audio output, weighted S/N ratio) better

than 60 dB (deviation 27 kHz) for 6 kHz sine wave black-to-white video modulation.

21. Measurements taken with SAW filter G3962 (Siemens) for vision IF (suppressed sound carrier) and G9350

22. The PC/SC ratio at pins 1 and 2 is calculated as the addition of TV transmitter PC/SC ratio and SAW filter PC/SC

ratio. This PC/SC ratio is necessary to achieve the S/N(W) values as noted. A different PC/SC ratio will change

these values.

23. Measurements taken with SAW filter L9453 (Siemens) for AM sound IF (suppressed picture carrier).

Table 1

Input frequencies and carrier ratios

Table 2

Switch logic

DESCRIPTION

SYMBOL B/G STANDARD

L STANDARD

L ACCENT

STANDARD

UNIT

Picture carrier

38.9

38.9

33.9

MHz

Sound carrier

33.4

32.4

40.4

MHz

33.158

−−

MHz

Picture-to-sound carrier ratio

13

10

10

dB

20

−−

dB

STANDARD SWITCH (PIN 7)

SELECTED STANDARD

VIDEO

POLARITY

FM-PLL

AF-AMPLIFIER

1212

B/G

negative

on

on

FM

FM

1.3 to 2.3 V

B/G, with external VIF-AGC

negative

on

on

FM

FM

0 to 0.8 V

L

positive

off

off

AM

mute