Kenwood TH-77A Service Manual page 27

IH-/f7A/E
SEMICONDUCTOR DATA
e@Block Diagram
P/N vec GND
Data latch (11-bit)
Test signa!
Lock —
Modulus Local oscillator
H pP 2 prescalers Fi OO PD
(1/128 and 1/127) programmable divider
REFC) I
'
C) sw2
'
|
>
C) swi
st©
Shift register (21-bit)
=
i
Phase
detector
Y
|
vec |
Latch signal
|
@Pin Functions
1 Si
2 CPS
Clock pulse input}
Shift register clock pulse input
Reset pulse :
input 21-pulse counter reset pulse input
4 REF
|_ Reference bias
Grounded by a 1000 pF capacitor.
5
FIN
ee oscillator | | cal oscillator frequency (VCO) input. 540 MHz (max)
6 Ne SW1 Output port 1
The output port status can be set by the transfer data from the controller.
ot
7 SW2 Output port 2
8 GND | Ground Ov
Phase detector |
9 P/N polarity selection
input
|
10
LFO
Filter output
Low-pass filter transistor collector output
LFI
a Filter input
Low-pass filter transistor base input
if A ae
PD Fase: derceven Tristate output
output
13
| Lock | beck detection | «1+. during PLL lock, "H": during unlock. Open collector
output
Crystal oscillator
[eon
Power
3.0~5.5 V
27