Tait TP9100 - Page 57

TP9100 Service Manual Circuit Descriptions 57
© Tait Electronics Limited May 2005
Figure 3.4 Block diagram of the frequency synthesizer circuitry
Buffer
Buffer
and
Sample
PLL
MOD
5 V SWITCH
SYN TX LO SYN RX LO1
TR Switch
DIG SYN TR SW
Signal Types:
RF analog clock digital asynchronous serial data synchronous serial data
PLL
Summer
Loop
Filter
VCO
Supply
Filter
+4 V DEC
Frequency Synthesizer
LPF
Mixer
VCXO
TCXO
Modulator Buffer Amplifier
PLL
VCO 1
5V
Switch
TR Switch
VCO (UHF only)
+5V0 AN AGND
Power
Supply
CDC VCXO MOD SYN CDC FCL SYN CDC LFV CDC VCO MOD
CODEC
and
Audio
SYN TX LO
SYN RX LO1
Trans-
mitter
SYN RX OSC
Receiver
Digital
DIG SYN SPI DO DIG SYN SPI CLK DIG SYN TR SW DIG SYN EN DIG SYN FAST DIG SYN LATCH SYN LOCK SYN DIG FREF
14 V
SMPS
Buffer Amplifier
Interfaces
Inverter
+7V5 LINK +3V0 AN +2V5CDC VCL SUPPLY
3 V Switch
+3V0 AN
+5V0 AN +3V0 AN
VCO 2
Buffer
Amplifier
Buffer
Amplifier
Sample
5 V Switch
VCO (VHF only)
MOD