tda8349a NXP Semiconductors, tda8349a Datasheet - Page 11

• Manufacturer Part Number: tda8349a
• Description: Multistandard If Amplifier And Demodulator
• Manufacturer: NXP Semiconductors

Philips Semiconductors
Notes
1. All input signals are measured in RMS values at 100% carrier level and a frequency of 38.9 MHz.
2. On set AGC.
3. Input impedance selected so that a SAW filter can be applied without extra components.
4. Measured with 0 dB = 200 V.
5. Measured at 10 mV(RMS) top sync input signal and the video output unloaded.
6. Projected zero point with internally switched demodulator.
7. With the AGC switch switched to ground, for the B/G standard, or with the identification capacitor switched to V
8. With the AGC switch switched open for the L standard, or switched to V
9. Measured in accordance with the test line given in Fig.8.
10. Measured in accordance with the test line shown in Fig.9.
11. Measured with a 75
12. The internal circuit of pin 20 behaves as an internal voltage source of 4.5 V with an input resistance of 15 k . Using
13. Measured with a capacitor of 2.2 F connected to pin 5. A step is made from 200 V to 80 mV input signals.
14. Measured with a capacitor of 2.2 F connected to pin 5. A step is made from 80 mV to 200 V input signals.
15. It is possible to adjust the tuner AGC over the whole AGC range of the IF amplifier for both pnp and npn tuners. Tuner
16. Crosstalk is defined as:
17. The video switch is controlled by a voltage on pin 7. The switching level is approximately 1.4 V. With pin 7 open-circuit
18. Measurement taken with an input 10 mV(RMS). The unloaded Q factor of the reference tuned circuit is 70.
19. Switching off the AFC is obtained by a voltage of less than 2 V on pin 6. Normally this is achieved by pulling pin 6 to
20. Switching to the normal analog AFC mode can be done by pulling pin 9 to a voltage above 10.2 V. Normally this is
February 1991
Multistandard IF amplifier and demodulator
for the negative MAC standard.
-
-
The non-linearity is measured by comparing the differences between adjacent pairs of six luminance levels that make
up the 5 step staircase. The measurement result is the largest percentage deviation in adjacent step values. The sign
is always positive.
the system switch three conditions can be obtained:
Negative modulation with top sync level AGC. This is achieved with pin 20 connected to ground.
Positive modulation with white level AGC. This is achieved with pin 20 open, or connected to 5 V.
Positive modulation with top white AGC and an increased time constant for MAC signals. This is achieved with pin
20 connected to V
AGC starting point is defined as an output current of 0.2 mA for pnp and 1.8 mA for npn, in an application with a
resistance of 6 k to V
internal video is selected; with pin 7 pulled to ground external video is selected.
ground.
achieved by pulling pin 9 to V
The inverse analog AFC mode can only be obtained by a voltage of between 8 and 10 V applied to pin 9.
The differential gain is expressed as a percentage of the difference in peak amplitudes between the largest and
smallest value relative to the subcarrier amplitude at blanking level.
The differential phase is defined as the difference in degrees between the phase angle of the 4.4 MHz signal at
20% and 80% luminance signal.
CC
.
source:
P
20 log
at pin 4.
P
S N
.
V
--------------------------------------------------------------------------------------- measured at 4.4 MHz
V
o
unwanted video black-to-white
o
wanted video black-to-white
=
20
log
-------------------------------------------------------------- -
V
n
V
RMS at B = 5 MHz
o
black-to white
11
CC
for the positive MAC standard.
Product specification
TDA8349A
CC