Datasheet
Data Sheet AD9518-4
Rev. B | Page 45 of 64
CONTROL REGISTERS
CONTROL REGISTER MAP OVERVIEW
Table 42. Control Register Map Overview
Reg.
Addr.
(Hex)
Parameter Bit 7 (MSB) Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 (LSB)
Default
Value
(Hex)
Serial Port Configuration
0x000 Serial port
configuration
SDO
active
LSB first Soft reset Long
instruction
Long
instruction
Soft reset LSB first SDO active 0x18
0x001 Blank
0x002 Reserved
0x003 Part ID Part ID (read only) 0xE3
0x004 Readback
control
Blank Read back
active
registers
0x00
PLL
0x010 PFD and
charge pump
PFD
polarity
Charge pump current Charge pump mode PLL power-down 0x7D
0x011 R counter 14-bit R divider, Bits[7:0] (LSB) 0x01
0x012 Blank 14-bit R divider, Bits[13:8] (MSB) 0x00
0x013 A counter Blank 6-bit A counter 0x00
0x014 B counter 13-bit B counter, Bits[7:0] (LSB) 0x03
0x015 Blank 13-bit B counter, Bits[12:8] (MSB) 0x00
0x016 PLL Control 1 Set CP pin
to V
CP
/2
Reset R
counter
Reset A and
B counters
Reset all
counters
B counter
bypass
Prescaler P 0x06
0x017 PLL Control 2 STATUS pin control Antibacklash pulse width 0x00
0x018 PLL Control 3 Reserved Lock detect counter Digital lock
detect
window
Disable
digital lock
detect
VCO calibration divider VCO cal now 0x06
0x019 PLL Control 4 R, A, B counters
SYNC
pin reset
R path delay N path delay 0x00
0x01A PLL Control 5 Reserved Reference
frequency
monitor
threshold
LD pin control 0x00
0x01B PLL Control 6 VCO
frequency
monitor
REF2
(
REFIN
)
frequency
monitor
REF1 (REFIN)
frequency
monitor
REFMON pin control 0x00
0x01C PLL Control 7 Disable
switchover
deglitch
Select
REF2
Use
REF_SEL pin
Reserved REF2
power-on
REF1
power-on
Differential
reference
0x00
0x01D PLL Control 8 Reserved PLL status
register
disable
LD pin
comparator
enable
Holdover
enable
External
holdover
control
Holdover
enable
0x00
0x01E PLL Control 9 Reserved 0x00
0x01F PLL readback Reserved VCO cal
finished
Holdover
active
REF2
selected
VCO
frequency >
threshold
REF2
frequency >
threshold
REF1
frequency >
threshold
Digital
lock detect
N/A
0x020
to
0x04F
Blank
0x0A0
to
0x0AB
Reserved
0x0AC
to
0x0EF
Blank