3X8168 Datasheet, PDF (7/14 Pages) List of Unclassifed Manufacturers – TARGET SPECIFICATION ELECTRICAL DATA

8. I²C bus
There are two different I²C bus used one I²C Tuner to control tuning and one I²C IF to control IF
demodulation and baseband processing. With port P0 of control byte 2 the slave address of I²C IF can be
controlled.
8.1 I²C Tuner
8.1.1 Write data format
MSB
LSB
Address byte
1
1
0
0
0
MA1 MA0 R/W A
Divider byte 1
0
n14 n13
n12
n11
n10
n9
n8
A
Divider byte 2
n7
n6
n5
n4
n3
n2
n1
n0
A
Control byte 1
1
CP
T2
T1
T0
RSA RSB OS A
Control byte 2
P7
P6
P5
P4
P3
P2
P1
P0 A
A = Acknowledge
R/W = 0 : Write mode
CP = 1 : charge pump current high
T2, T1, T0 = test bits, normal operation: T2 = 0, T1 = 0, T0 = 1
RSA, RSB bits for minimum step size, see 8.1.2
OS = tuning voltage switch, normal operation: OS = 0
8.1.2 Address selection
MA1
0
0
1
1
MA0
0
1
0
1
Address
C0
C2
C4
C6
Voltage at Pin 11
( 0 to 0.1 ) * V_S1
(0.2 to 0.3) * V_S1 or open
( 0.4 to 0.6 ) * V_S1
( 0.9 to 1 ) * V_S1
8.1.3 Oscillator frequency and divider byte calculation:
RSA
RSB
Reference divider
Min. tuning step [kHz]
1
1
512
62.5
X
0
640
50.0
0
1
1024
31.25
for FM recption we recommend 50 kHz minimum step size
fref [kHz]
7.8125
6.25
3.90625
f_OSC= f_D + f_IF
f_IF = 38.9 MHz at B/G, D/K, I, L
f_IF = 33.9 MHz at L’
f_IF = 33.3 MHz at FM
f_OSC : Local oscillator frequency
f_D : Desired frequency
f_OSC = f_REF * 8 * SF
f_REF : Crystal reference frequency / 640 = 4 MHz / 640 = 6.25 kHz, ( RSA =X, RSB = 0)
SF : Programmable scaling factor
Scaling factor
SF= 16384* n14 + 8192 * n13 * 4096 * n12 + 2048 * n11 + 1024 * n10 + 512 * n9 + 256* n8 + 128 * n7 +
64 * n6 + 32 * n5 + 16 * n4 + 8 * n3 + 4 * n2 + 2 * n1 + n0
3X8168 ED
November 02
Page: 7/14
8168ED01.DOC