AK1548 Datasheet, PDF (29/42 Pages) Asahi Kasei Microsystems – 8GHz Low Noise Integer-N Frequency Synthesizer

[AK1548]
FAST[1:0] : Enables or disables the Fast Lock mode
When {FAST[1:0]} is ”11Bin”, {CPGAIN} of function latch is the Fast Lock mode bit. When Fast Lock is
enabled, charge pump current is set to the value of {CP2} setting during the switchover time under the
control of the timer counter. After the timeout, {CPGAIN} is reset into “0” and charge pump current goes
to be {CP1} setting value.
D8 D7 {CPGAIN}
0
X0
1
0
01
1
0
11
1
Function
{CP1} is enabled
{CP2} is enabled
{CP1} is enabled
{CP2} is enabled
{CP1} is enabled
{CP2} is enabled, and
switchover operates.
Remarks
{CPGAIN} is reset to “0” after
timeout.
CPHIZ : TRI-STATE output setting for charge pump
D6
Function
Remarks
0
Charge pumps are activated. Use this setting for normal operation.
1
TRI-STATE
Note 1)
Note 1) The charge pump output is turned OFF and put in the high-impedance (Hi-Z)
state.
CPPOLA : Selects positive or negative output polarity for CP1 and CP2
D5
Function
0
Negative
1
Positive
Remarks
MS1364-E-00
29
2012/1