
1998 Feb 11
18
Philips Semiconductors
Product specification
Multistandard/MAC VIF-PLL with QSS-IF
and dual FM-PLL/AM demodulator
TDA9815
4.
Loop bandwidth BL = 75 kHz (natural frequency f
n
= 11 kHz; damping factor d
≈
3.5; calculated with sync level within
gain control range). Resonance circuit of VCO: Q
0
> 50; C
ext
= 8.2 pF
±
0.25 pF; C
int
≈
8.5 pF (loop voltage
approximately 2.7 V).
Temperature coefficient of external LC-circuit is equal to zero.
V
i IF
= 10 mV RMS;
f = 1 MHz (VCO frequency offset related to picture carrier frequency); white picture
video modulation.
V
i IF
signal for nominal video signal.
Measurements taken with SAW filter G3962 (sound carrier suppression: 40 dB); loop bandwidth BL = 75 kHz:
a) Modulation VSB; sound carrier
off
; f
video
> 0.5 MHz.
b) Sound carrier
on
; SIF SAW filter L9453; f
video
= 10 kHz to 10 MHz.
The 7 dB buffer gain accounts for 1 dB loss (not valid for MAC) in the sound trap. Buffer output signal is typical
2 V (p-p), in event of CVBS video amplifier output typical 1 V (p-p). If no sound trap is applied a 330
resistor must
be connected from output to input (from pin 21 to pin 22).
10. The leakage current of the AGC capacitor should not exceed 1
μ
A at B/G standard respectively 10 nA current at
L standard. Larger currents will increase the tilt.
11. S/N is the ratio of black-to-white amplitude to the black level noise voltage (RMS value, pin 10). B = 5 MHz weighted
in accordance with “CCIR 567”
5.
6.
7.
8.
9.
12. The intermodulation figures are defined:
V
at 4.4 MHz
V
0
at 1.1 MHz
V
at 4.4 MHz
V
0
at 3.3 MHz
; α
1.1
value at 1.1 MHz referenced to black/white signal;
3.6dB
; α
3.3
value at 3.3 MHz referenced to colour carrier.
13. Response speed valid for a VIF input level range of 200
μ
V up to 70 mV.
14. To match the AFC output signal to different tuning systems a current source output is provided. The test circuit is
given in Fig.7. The AFC-steepness can be changed by the resistors at pin 23.
15. Depending on the ratio
C/C
0
of the LC resonant circuit of VCO (Q
0
> 50; see note 4; C
0
= C
int
+ C
ext
).
16. Input level for second IF from an external generator with 50
source impedance. AC-coupled with 10 nF capacitor,
f
mod
= 1 kHz, 27 kHz (54% FM deviation) of audio references. A VIF/SIF input signal is not permitted. Pins 8 and 28
have to be connected to positive supply voltage for minimum IF gain. S/N and THD measurements are taken at 50
μ
s
de-emphasis. The not tested FM-PLL has to be locked to an unmodulated carrier.
a) Second IF input level 10 mV RMS.
17. Measured with an FM deviation of 27 kHz the typical AF output signal is 500 mV RMS (R
x
= R
y
= 0
; see Fig.13).
By using R
x
= R
y
= 470
the AF output signal is attenuated by 6 dB (250 mV RMS) and adapted to the stereo
decoder family TDA9840. For handling an FM deviation of more than 53 kHz the AF output signal has to be reduced
by using R
x
and R
y
in order to avoid clipping (THD < 1.5%). For an FM deviation up to 100 kHz an attenuation of 6 dB
is recommended with R
x
= R
y
= 470
.
18. The leakage current of the decoupling capacitor (2.2
μ
F) should not exceed 1
μ
A.
19. In the event of activated auto mute state the second FM-PLL oscillator is switched off, if the input signal at pin 16 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 16 disables the mute state (at low SIF input signal),
but this will not lead to false identification of the used stereo decoder family TDA9840.
α
1.1
20
-------------------------------------
+
log
=
α
3.3
20
-------------------------------------
log
=