FEBRUARY 1994
ADVANCE INFORMATION
D.S. 3931 1.5
SP5654
2.7GHz 3–WIRE BUS CONTROLLED SYNTHESISER
The SP5654 is a single chip frequency synthesiser
designed for satellite TV tuning systems. It is a programming
variant of the SP5655 allowing the design of one tuner with
either I
2
C bus or a 3–wire bus format depending on which
device is inserted. The device when used with a varicap tuner,
forms a complete phase locked loop tuning system. The circuit
consists of a divide–by–16 prescaler with its own preamplifier
and a 14/15 bit programmable divider controlled by a serially
loaded data register. Four independently programmable open
collector outputs are included. The device contains five modes
of operation each compatible with Toshiba 18 and 19 bit
software.
The comparison frequencies are obtained from a crystal
controlled on–chip oscillator typically operating at 4MHz. The
comparator has a charge pump output amplifier stage around
which feedback may be applied. Only one external transistor
is required for varicap line driving.
CHARGE PUMP
CRYSTAL
MODE SELECT
DATA
CLOCK
PORT P3
PORT P2
PORT P1
1
16
DRIVE OUTPUT
V
EE
S
P
5
6
5
4
RF INPUT
RF INPUT
V
CC
LOCK
ENABLE
PORT P0
FEATURES
J
Complete 2.7GHz Single Chip System
J
High Sensitivity RF Input
J
Low power Consumption (5V, 30mA)
J
On–Chip Oscillator with 1kW negative resistance
J
On chip oscillator start–up circuit
J
Programming Compatible with Toshiba TD6380,
TD6381 and TD6382#
J
Pin compatible with SP5655#
J
5 Modes of Operation with different step sizes,
see Table 1; each selectable with 18 or 19 bit
transmission length.
J
Single Port 18/19 Bit Serial Data Entry
J
Auto select for Data transmission length, 18 or 19
J
Low Radiation
J
Phase Lock Detector
J
Varactor Drive Amp Disable
J
Charge Pump Disable
J
Four Controllable Outputs
J
ESD Protection
[
# See notes on pin and programming compatibility
[
Normal ESD handling procedures should be
observed.
MP16
Fig.
1 Pin connections – top view
APPLICATIONS
J
Satellite TV
J
High IF Cable Tuning Systems
ORDERING INFORMATION
SP5654/KG/MPAS (Tubes)
SP5654/KG/MPAD (Tape and Reel)
ZARLINK [ ZARLINK SEMICONDUCTOR INC ]
