TDA6402 Datasheet, PDF (28/40 Pages) NXP Semiconductors – 5 V mixers/oscillators and synthesizers for cable TV and VCR 2-band tuners

Philips Semiconductors
5 V mixers/oscillators and synthesizers for
cable TV and VCR 2-band tuners
Product specification
TDA6402; TDA6402A;
TDA6403; TDA6403A
Table 18 Crystal
COMPONENT
X1
VALUE
4 MHz
Table 19 Transistors
COMPONENT
TR1
TR2
VALUE
BC847B
BC847B
Tuning amplifier
The tuning amplifier is capable of driving the varicap
voltage without an external transistor. The tuning voltage
output must be connected to an external load of 27 kΩ
which is connected to the tuning voltage supply rail.
The loop filter design depends on the oscillator
characteristics and the selected reference frequency.
Examples of I²C-bus sequences (SW = V_CC) for
TDA6402 and TDA6403
Tables 20 to 24 show the various sequences where:
f_OSC = 100 MHz
PVHFL = ‘ON’ to switch on VHF I
FMST is ‘ON’ to switch on an FM sound trap
I_CP = 280 µA
N = 512
f_XTAL = 4 MHz
S = START
A = acknowledge
P = STOP.
For the complete sequence see Table 20 (sequence 1) or
Table 21 (sequence 2).
Crystal oscillator
The crystal oscillator uses a 4 MHz crystal connected in
series with an 18 pF capacitor thereby operating in the
series resonance mode. Connecting the oscillator to the
supply voltage is preferred, but it can also be connected to
ground.
Table 20 Complete sequence 1
START
S
ADDRESS BYTE DIVIDER BYTE 1 DIVIDER BYTE 2 CONTROL BYTE
C2
A
06
A
40
A
CE
A
BAND SWITCH
BYTE
09
A
STOP
P
Table 21 Complete sequence 2
START ADDRESS BYTE CONTROL BYTE
S
C2
A
CE
A
BAND SWITCH
BYTE
09
A
DIVIDER BYTE 1 DIVIDER BYTE 2
06
A
40
A
STOP
P
Table 22 Divider bytes only sequence
S C2 A 06 A 40 A P
Table 23 Control and band switch bytes only sequence
S C2 A CE A 09 A P
Table 24 Control byte only sequence
S
C2
A
CE
A
P
Table 25 Status byte acquisition
S
C3
A
XX⁽¹⁾
X⁽²⁾
P
Notes
1. XX = Read status byte.
2. X = No acknowledge from the master means end of
sequence.
2000 Jan 24
28