NEC PD17062 Manuale Utente

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PD17062
18.3   PROGRAMMABLE DIVIDER (PD) AND PLL MODE SELECT REGISTER
18.3.1   Programmable Divider Configuration
Fig. 18-2 shows the configuration of the programmable divider (PD).
As shown in Fig. 18-2, the programmable divider consists of a swallow counter and programmable counter.
Fig. 18-2   Programmable Divider Configuration
0CH
0DH
0EH
0FH
DBF3
DBF2
DBF1
DBF0
M
S
B
L
S
B
16
12
4
PSC
VCO
Data buffer (DBF)
Address
Symbol
Data
PLL data register
12 bits
4 bits
Swallow counter
4 bits
Programmable counter
12 bits
f
N
To    -DET   
φ
1/2 frequency 
divider
PLL disable signal