AK1547 Datasheet, PDF (23/37 Pages) Asahi Kasei Microsystems – 4GHz Low Noise Integer-N Frequency Synthesizer

[AK1547]
< Address2 : Function >
D[21:20] D19 D[18:16] D[15:13] D[12:9]
D[8:7]
PRE[1:0] PD2 CP2[2:0] CP1[2:0] TIMER[3:0] FAST[1:0]
D6
D5
D[4:2]
D1
D0
Address
CPHIZ CPPOLA LD[2:0]
PD1
CNTR_RST
02
PRE[1:0] : Selects a dividing ratio for the prescaler
The prescaler value should be chosen so that the prescaler output frequency is always less than or
equal to 125MHz.
D21 D20
Function
Remarks
00
P=8, Dual modulus prescaler 8/9
01
P=16, Dual modulus prescaler 16/17
10
P=32, Dual modulus prescaler 32/33
11
P=64, Dual modulus prescaler 64/65
PD2, PD1 : Power Down Select
[PDN]
<Address2>
{PD2} {PD1}
Function
“Low”
X
X Power Down
“High”
X
0 Normal Operation
“High”
0
1 Asynchronous Power Down
“High”
1
1 Synchronous Power Down
X : Don’t care ( “0” is recommended)
{PD2}=1 and {PD1}=1 : All circuits powers down at the timing when the Phase detector frequency
signal reverses.
{PD2}=0 and {PD1}=1 : All circuits goes into Power Down during the rise up of LE signal that latches
“1” into {PD1}.
The registers can be written even in [PDN]=0.
MS1464-E-00
23
2012/9