AK1541_17 Datasheet, PDF (4/37 Pages) Asahi Kasei Microsystems – 20 to 600Mhz Delta-Sigma Fractional-N Frequency Synthesizer

[AK1541]
4. Pin Functional Description
No. Name I/O
Table 1 Pin Function
Pin Functions
1 CPVDD P Power supply for charge pump
2 TEST4 DI Test pin 4
3 TEST1 DI Test pin 1
4 LE
DI Load enable
5 DATA DI Serial data input
6 CLK
DI Serial clock
7 LD
DO Lock detect
8 PDN2 DI Power down pin for PLL
9 PDN1 DI Power down signal for LDO
10 REFIN AI Reference input
11 TEST2 DI Test pin 2
12 TEST3 DI Test pin 3
13 VREF1 AIO Connect to LDO reference voltage capacitor
14 DVSS G Digital ground pin
15 VREF2 AIO Connect to LDO reference voltage capacitor
16 RFINN AI Prescaler input
17 RFINP AI Prescaler input
18 PVDD
19 BIAS
20 PVSS
P Power supply for peripherals
AIO
Resistance pin for setting charge pump output
current
G Ground pin for peripherals
21 CP
AO Charge pump output
22 CPZ
AIO Connect to the loop filter capacitor
23 SWIN AI Connect to resistance pin for fast lockup
24 CPVSS G Ground pin for charge pump
Power down
Remarks
“Low”
Internal pull-down,
Schmidt trigger input
Internal pull-down,
Schmidt trigger input
Schmidt trigger input
Schmidt trigger input
Schmidt trigger input
Schmidt trigger input
Schmidt trigger input
“Low”
Internal pull-down,
Schmidt trigger input
Internal pull-down,
Schmidt trigger input
“Low”
“Hi-Z”
Notes 1) & 2)
Notes 1) & 2)
Note 1) For detailed functional descriptions, see the section “Charge Pump and Loop Filter” in “8. Block Functional
Description” below.
Note 2) The input voltage from the [CPZ] pin is used in the internal circuit. The [CPZ] pin must not be open even
when the fast lockup feature is unused. For the output destination from the [CPZ] pin, see “P.12 Fig.5 Loop
MS1043-E-05
4
2013/03