U6225B Datasheet, PDF (6/12 Pages) TEMIC Semiconductors – 2.9 GHz PLL for SAT TV Receiver with Universal Bus

U6225B
TELEFUNKEN Semiconductors
riod, and then also during the acknowledge periods, when
additional data bytes are programmed. After the address
transmission (first byte), data bytes can be sent to the de-
vice. There are four data bytes requested to fully program
the device. The table ‘I²C-Bus Pulse Diagram’ shows
some possible data transfer examples.
Programmable divider bytes PDB1 and PDB2 are stored
in a 15 bit latch and are controlling the division ratio of
the 15 bit programmable divider. The control Byte CB1
allows to control the following special functions:
D 5I-bit switches between low and high charge pump
current
D T1-bit enables divider test mode when it is set to
logic 1
D T0-bit allows to disable the charge pump when it is set
to logic 1
D OS-bit disable the charge pump drive amplifier output
when it is set to logic 1.
Only in I²C bus mode the charge pump current can be con-
trolled. In 3-wire-bus mode there is always the high
charge pump current active. The OS-bit function disables
the complete PLL function. This allows the tuner align-
ment by suppling the tuning voltage directly through the
30 V supply voltage of the tuner.
The control byte CB2 programs the switching outputs SW
1, 4, 5, 6, 7; a logic 0 for high impedance output (off) and
a logic 1 for low impedance output (on).
Description
Address byte
Progr. divider byte 1
Progr. divider byte 2
Control byte 1
Control byte 2
I²C Bus Data Format
MSB
LSB
1
1
0
0
0 AS1 AS2 0
A
0 n14 n13 n12 n11 n10 n9 n8 A
n7 n6 n5 n4 n3 n2 n1 n0 A
1
5I T1 T0 X
X
X OS A
SW7 SW6 SW5 SW4 X
X SW1 X
A
A = Acknowledge; X = not used; Unused bits of controlbyte 2 should be 0 for lowest power consumption
n0 ... n14
T0, T1
Scaling factor (SF)
Testmode selection
SW1, 4, 5, 6, 7
5I
OS
AS1, AS2
Switching outputs
Charge pump current switch
Output switch
Address selection pin 10
SF = 16384*n14+8192*n13+ ... +2*n1 + n0
T1 = 1: divider test mode on
T1 = 0: divider test mode off
T0 = 1: charge pump disable
T0 = 0: charge pump enable
SW1, SW4, SW5, SW6, SW7 = 1: open collector active
5I = 1: high current
5I = 0: low current
OS = 1: varicap driver disable
OS = 0: varicap drive enable
AS1 AS2 Address
01
1
00
2
10
3
11
4
Dec. Value
194
192
196
198
Voltage at pin
10
open
0 to 10% Vs
40 to 60% Vs
90 to 100% Vs
6 (12)
Rev. A1: 25.10.1995