TDA8722 Datasheet, PDF (15/28 Pages) NXP Semiconductors – I2C-bus programmable modulator for negative video modulation and FM sound

Philips Semiconductors
I²C-bus programmable modulator for
negative video modulation and FM sound
APPLICATION INFORMATION
Product specification
TDA8722
handbook, full pagewidthR20
VIDEO _{470 Ω}
100 nF
C19
R18
82 Ω
R19
470 Ω
100 nF
C20
RF
75 Ω
R15
75 Ω
15 pF _R17
C17 ^{120 kΩ}
100 pF 100 pF
C16
C15
1 kΩ
R14
PORT
SCL
SDA
20
19 18
12
3
K1 ⁽¹⁾
AUDIO
C1
R4
220 Ω
220 pF
R1
220 kΩ
R2
12 kΩ
C3
56 pF
R3
15 kΩ
L3⁽³⁾
15 µH
K2(4)
17
16
15
14 13 12 11
TDA8722
4
56
78
9 10
L5 ⁽²⁾
33 pF
C5
D5
33 pF
C6
BB215
R5
22 kΩ
R6
22 kΩ
R7
150 nF
C8
R8
12 kΩ
R9
22 kΩ
10 nF
C7
12 kΩ
T8
BC547B
10 nF
C11
Q9
4 MHz
27 pF
C9
33 V
5V
C30
10 nF
C31
C21
2.2 µF 2.2 µF
MBE403
GND
(1) K1: switches the pre-emphasis filter on or off.
(2) L5: air coil; 1.5 turns; diameter of 2 mm.
(3) L3: to adjust the application to the right sound carrier frequency (5.5 MHz for PAL G).
(4) K2: Switches the FM sound oscillator on or off.
Fig.7 Reference measuring set-up.
1998 Jun 23
15