AD9518-1A/PCBZ Analog Devices Inc, AD9518-1A/PCBZ Datasheet - Page 53

• Manufacturer Part Number: AD9518-1A/PCBZ
• Description: 6-Output Clock Generator With 2.8GHz
• Manufacturer: Analog Devices Inc

Specifications of AD9518-1A/PCBZ

• Main Purpose: Timing, Clock Generator
• Embedded: No
• Utilized Ic / Part: AD9518-1A
• Primary Attributes: 2 Inputs, 6 Outputs, 2.5GHz VCO
• Secondary Attributes: LVPECL Output Logic
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Reg.
Addr.
(Hex)
0x01C
0x01D
0x01F
Bits
7
6
5
4
3
2
1
0
3
2
1
0
6
5
4
3
4
Name
Disable
switchover
deglitch
Select REF2
Use REF_SEL pin
Automatic
reference
switchover
Stay on REF2
REF2 power-on
REF1 power-on
Differential
reference
PLL status
register disable
LD pin comparator
enable
Holdover enable
External
holdover control
Holdover enable
VCO cal finished
Holdover active
REF2 selected
VCO frequency >
threshold
Description
Disables or enables the switchover deglitch circuit.
0: enables switchover deglitch circuit (default).
1: disables switchover deglitch circuit.
If Register 0x01C, Bit 5 = 0, select reference for PLL.
0: selects REF1 (default).
1: selects REF2.
If Register 0x01C, Bit 4 = 0 (manual), sets method of PLL reference selection.
0: uses Register 0x01C, Bit 6 (default).
1: uses REF_SEL pin.
Automatic or manual reference switchover. Single-ended reference mode must be selected by Register 0x01C, Bit 0 = 0.
0: manual reference switchover (default).
1: automatic reference switchover.
Stays on REF2 after switchover.
0: returns to REF1 automatically when REF1 status is good again (default).
1: stays on REF2 after switchover. Does not automatically return to REF1.
When automatic reference switchover is disabled, this bit turns the REF2 power on.
0: REF2 power off (default).
1: REF2 power on.
When automatic reference switchover is disabled, this bit turns the REF1 power on.
0: REF1 power off (default).
1: REF1 power on.
Selects the PLL reference mode, differential or single-ended. Single-ended must be selected for the automatic
switchover or REF1 and REF2 to work.
0: single-ended reference mode (default).
1: differential reference mode.
Disables the PLL status register readback.
0: PLL status register enable (default).
1: PLL status register disable.
Enables the LD pin voltage comparator. This function is used with the LD pin current source lock detect mode. When
in the internal (automatic) holdover mode, this function enables the use of the voltage on the LD pin to determine if
the PLL was previously in a locked state (see
STATUS pins to monitor the voltage on this pin.
0: disables LD pin comparator; internal/automatic holdover controller treats this pin as true (high) (default).
1: enables LD pin comparator.
Along with Bit 0, enables the holdover function. Automatic holdover must be disabled during VCO calibration.
0: holdover disabled (default).
1: holdover enabled.
Enables the external hold control through the SYNC pin. (This disables the internal holdover mode.)
0: automatic holdover mode; holdover controlled by automatic holdover circuit (default).
1: external holdover mode; holdover controlled by SYNC pin.
Along with Bit 2, enables the holdover function. Automatic holdover must be disabled during VCO calibration.
0: holdover disabled (default).
1: holdover enabled.
Read-only register. Indicates status of the VCO calibration.
0: VCO calibration not finished.
1: VCO calibration finished.
Read-only register. Indicates if the part is in the holdover state (see
0: not in holdover.
1: holdover state active.
Read-only register. Indicates which PLL reference is selected as the input to the PLL.
0: REF1 selected (or differential reference if in differential mode).
1: REF2 selected.
Read-only register. Indicates if the VCO frequency is greater than the threshold (see
frequency status monitor).
0: VCO frequency is less than the threshold.
1: VCO frequency is greater than the threshold.
Rev. A | Page 53 of 64
Figure 37
). Otherwise, this function can be used with the REFMON and
Figure 37
). This is not the same as holdover enabled.
Table 15
, REF1, REF2, and VCO
AD9518-1