tda9808t NXP Semiconductors, tda9808t Datasheet - Page 17

• Manufacturer Part Number: tda9808t
• Description: Single Standard Vif-pll With Qss-if And Fm-pll Demodulator
• Manufacturer: NXP Semiconductors

Philips Semiconductors
11. Measurements taken with SAW filter M3951 (sound carrier suppression: 32 dB); loop bandwidth BL = 70 kHz:
12. Response speed valid for a VIF input level range of 200 V up to 70 mV.
13. To match the AFC output signal to different tuning systems a current source output is provided. The test circuit is
14. Depending on the ratio C/C
15. Source impedance: 2.3 k in parallel to 12 pF (SAW filter); f
16. Input level for second IF from an external generator with 50
17. Measured at de-emphasis circuitry with an FM deviation of 25 kHz (f
18. The leakage current of the decoupling capacitor (22 F) should not exceed 1 A.
19. For all S/N measurements the used vision IF modulator has to meet the following specifications:
20. The PC/SC
21. Measurements taken with SAW filter M3951 for vision IF (suppressed sound carrier, minimum 25 dB) and M9352 for
Table 1 Input frequencies and carrier ratios
1999 Jun 04
f
f
f
SC
SC
pc
SC1
SC2
Single standard VIF-PLL with QSS-IF and
FM-PLL demodulator
or f
a) Modulation VSB; sound carrier off; f
b) Sound carrier on; SIF SAW filter M9352; f
given in Fig.10. The AFC-steepness can be changed by the resistors at pin 13.
f
have to be connected to positive supply voltage for minimum IF gain. S/N and THD measurements are taken at
75 s de-emphasis (modulator pre-emphasis has to be activated). The FM demodulator steepness V
positive.
a) Second IF input level 10 mV RMS.
500 mV RMS (R
For handling a frequency deviation of more than 53 kHz the AF output signal has to be reduced by using R
to avoid clipping (THD < 1.5%). For an FM deviation up to 100 kHz an attenuation of 6 dB is recommended with
R
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
c) Picture-to-sound carrier ratio; PC/SC
This PC/SC
values.
sound IF (suppressed picture carrier). Input level V
accordance with “CCIR 468-4” .
1
2
mod
x
SYMBOL
= 470 .
IF
than 60 dB (deviation 25 kHz) for 6 kHz sine wave black-to-white video modulation.
= 400 Hz, 25 kHz (50% FM deviation) of audio reference. A VIF/SIF input signal is not permitted. Pins 5 and 17
1
1
ratio is calculated as the addition to TV transmitter PC/SC
ratio is necessary to achieve the S/N
x
= 0 ). By using R
picture/IF carrier
sound carrier
picture-to-sound carrier
DESCRIPTION
0
of the LC resonant circuit of VCO (Q
x
= 470
video
1
= 7 dB (transmitter).
> 0.5 MHz.
video
the AF output signal is attenuated by 6 dB (250 mV RMS).
W(audio)
= 10 kHz to 10 MHz.
i(SIF)(rms)
17
B/G STANDARD
values as noted. A different PC/SC
= 10 mV, 25 kHz (50% FM deviation). Measurements in
33.158
IF
38.9
33.4
source impedance, AC-coupled with 10 nF capacitor,
13
20
= 38.9 MHz.
0
mod
> 50; see note 4; C
1
= 400 Hz) the typical AF output signal is
ratio and SAW filter PC/SC
M, N STANDARD
45.75/58.75
41.25/54.25
0
7
= C
1
ratio will change these
int
Product specification
+ C
TDA9808
ext
1
).
ratio.
o(AF)
MHz
MHz
MHz
dB
dB
x
/ f
UNIT
in order
AF
is