AD9517-2_15 Datasheet, PDF (30/80 Pages) Analog Devices – 12-Output Clock Generator with Integrated 2.2 GHz VCO

AD9517-2
Data Sheet
REFIN (REF1)
REFIN (REF2)
BYPASS
LF
CLK
CLK
PD
SYNC
RESET
REF_ SEL
REF1
REF2
REFERENCE
SWITCHOVER
STATUS
STATUS
LOW DROPOUT
REGULATOR (LDO)
VCO
DIGITAL
LOGIC
VS GND
RSET
DISTRIBUTION
REFERENCE
REFMON
R
DIVIDER
VCO STATUS
P, P + 1
PRESCALER
A/B
COUNTERS
N DIVIDER
PROGRAMMABLE
R DELAY
PROGRAMMABLE
N DELAY
DIVIDE BY
2, 3, 4, 5, OR 6
10
DIVIDE BY
1 TO 32
CPRSET VCP
LOCK
DETECT
PHASE
FREQUENCY
DETECTOR
HOLD
CHARGE
PUMP
LVPECL
SCLK
SDIO
SDO
CS
SERIAL
CONTROL
PORT
DIVIDE BY
1 TO 32
DIVIDE BY
1 TO 32
DIVIDE BY
1 TO 32
LVPECL
∆T
LVDS/CMOS
∆T
LD
CP
STATUS
OUT0
OUT0
OUT1
OUT1
OUT2
OUT2
OUT3
OUT3
OUT4 (OUT4A)
OUT4 (OUT4B)
OUT5 (OUT5A)
OUT5 (OUT5B)
AD9517-2
DIVIDE BY
1 TO 32
DIVIDE BY
1 TO 32
OUT6 (OUT6A)
∆T
OUT6 (OUT6B)
LVDS/CMOS
OUT7 (OUT7A)
∆T
OUT7 (OUT7B)
Figure 44. Internal VCO and Clock Distribution
Internal VCO and Clock Distribution
When using the internal VCO and PLL, the VCO divider must
be employed to ensure that the frequency presented to the channel
dividers does not exceed their specified maximum frequency of
1600 MHz (see Table 3). The internal PLL uses an external loop
filter to set the loop bandwidth. The external loop filter is also
crucial to the loop stability.
When using the internal VCO, it is necessary to calibrate the
VCO (Register 0x018[0]) to ensure optimal performance.
For internal VCO and clock distribution applications, use the
register settings that are shown in Table 24.
Table 24. Settings When Using Internal VCO
Register
Function
0x010[1:0] = 00b PLL normal operation (PLL on).
0x010 to 0x01D
PLL settings. Select and enable a reference
input; set R, N (P, A, B), PFD polarity, and ICP
according to the intended loop configuration.
0x018[0] = 0b,
0x232[0] = 1b
Reset VCO calibration. This is not required
the first time after power-up, but it must be
performed subsequently.
0x1E0[2:0]
Set VCO divider to divide-by-2, divide-by-3,
divide-by-4, divide-by-5, and divide-by-6.
0x1E1[0] = 0b
Use the VCO divider as the source for the
distribution section.
0x1E1[1] = 1b
Select VCO as the source.
0x018[0] = 1b,
0x232[0] = 1b
Initiate VCO calibration.
Rev. E | Page 30 of 80