22

TK-480/481
SEMICONDUCTOR DATA
PLL System : SA7025DK (TX-RX Unit IC11)

■Block diagram

■Pin description

Pin No.

Symbol Description

1 CLOCK Serial clock input.

2 DATA Serial data input.

3 STROBE Serial strobe input.

4VSS Digital ground.
5RFIN Prescaler positive input.
6RFIN Prescaler negative input.
7VCCP Prescaler positive supply voltage. This pin supplies power to the prescaler and RF input buffer.

8 REFIN Reference divider input.

9 RA Auxiliary current setting; resistor to VSSA.

10 AUXIN Auxiliary divider input.

11 PHA Auxiliary phase detector output.

12 VSSA analog ground.

13 PHI Integral phase detector output.

14 PHP Proportional phase detector output.

15 VDDA

Analog supply voltage. This pin supplies power to the charge pumps, Auxiliary prescaler, Auxiliary and Reference buffers.

16 RN Main current setting; resistor to VSSA.

17 RF

Fractional compensation current setting; resistor to V

SSA

.

18 LOCK Lock detector output.

19 TEST Test pin; connect to VDD.

20 VDD Digital supply voltage. This pin supplies power to the CMOS digital part of the device.

CLOCK
DATA
STROBE
64/65/72
Prescaler Main dividers
PR NM1
NM2
NM3
12 8
2
2
FBEM
Fractional
accumulator
FMOD NF
3
Prescaler
modulus control
FB
Main phase
detector
Normal output
charge pump
Reference divider ÷2÷2÷2
Main
reference
select
EM
EM÷EA NR
12
SM
2
Auxiliary
reference
select
SA
2
Auxiliary
phase
detector
EA
EA
1/4
Prescaler Auxiliary divider
PA NA
12
Auxiliary output
charge pump
Integral output
charge pump
Speed-up
output
charge pump
2
FRD
CN
8
CL
2
CK
4
Serial input + Program latches
RF
IN
RF
IN
TEST
Vss
REF
IN
V
CCP
AUX
IN
V
DDA
V
SSA
V
DD
RF
RN
PHP
PHI
RA
PHA
LOCK