AD9518-4
Data Sheet
SPECIFICATIONS
Typical values are given for VS = VS_LVPECL = 3.3 V 5%; VS ≤ VCP ≤ 5.25 V; TA = 25°C; RSET = 4.12 kΩ; CPRSET = 5.1 kΩ, unless otherwise noted.
Minimum and maximum values are given over full VS and TA (−40°C to +85°C) variation.
POWER SUPPLY REQUIREMENTS
Table 1.
Parameter
Min
3.135
2.375
VS
Typ
Max
3.465
VS
Unit
V
V
V
kΩ
kΩ
Test Conditions/Comments
3.3 V 5ꢀ
Nominally 2.5 V to 3.3 V 5ꢀ
Nominally 3.3 V to 5.0 V 5ꢀ
Sets internal biasing currents; connect to ground
Sets internal CP current range, nominally 4.8 mA (CP_lsb = 600 μA);
actual current can be calculated by CP_lsb = 3.06/CPRSET;
connect to ground
VS
VS_LVPECL
VCP
RSET Pin Resistor
CPRSET Pin Resistor
3.3
5.25
4.12
5.1
2.7
10
BYPASS Pin Capacitor
220
nF
Bypass for internal LDO regulator; necessary for LDO stability;
connect to ground
PLL CHARACTERISTICS
Table 2.
Parameter
Min
1450
0.5
Typ
Max
Unit
Test Conditions/Comments
VCO (ON-CHIP)
Frequency Range
1800
MHz
MHz/V
V
See Figure 11
See Figure 6
VCO Gain (KVCO
)
50
Tuning Voltage (VT)
VCP
0.5
−
VCP ≤ VS when using internal VCO; outside of this range, the CP
spurs may increase due to CP up/down mismatch
Frequency Pushing (Open-Loop)
Phase Noise at 100 kHz Offset
Phase Noise at 1 MHz Offset
REFERENCE INPUTS
1
MHz/V
dBc/Hz f = 1625 MHz
dBc/Hz f = 1625 MHz
−109
−128
REFIN
Differential mode (can accommodate single-ended input
Differential Mode (REFIN,
)
by ac grounding undriven input)
Input Frequency
0
250
MHz
Frequencies below about 1 MHz should be dc-coupled;
be careful to match VCM (self-bias voltage)
Input Sensitivity
250
mV p-p PLL figure of merit (FOM) increases with increasing slew rate
(see Figure 10); the input sensitivity is sufficient for ac-coupled
LVPECL and LVDS signals
Self-Bias Voltage, REFIN
REFIN
1.35
1.30
4.0
1.60
1.50
4.8
1.75
1.60
5.9
V
V
Self-bias voltage of REFIN1
Self-Bias Voltage,
Input Resistance, REFIN
REFIN
REFIN1
Self-bias voltage of
Self-biased1
kΩ
kΩ
Input Resistance,
Self-biased1
4.4
5.3
6.4
Dual Single-Ended Mode (REF1, REF2)
Input Frequency (AC-Coupled)
Input Frequency (DC-Coupled)
Input Sensitivity (AC-Coupled)
Input Logic High
Two single-ended CMOS-compatible inputs
Slew rate > 50 V/μs
Slew rate > 50 V/μs; CMOS levels
Should not exceed VS p-p
20
0
250
250
MHz
MHz
V p-p
V
0.8
2.0
Input Logic Low
0.8
V
Input Current
Pulse Width High/Low
−100
1.8
+100
μA
ns
This value determines the allowable input duty cycle and is the
amount of time that a square wave is high/low
Input Capacitance
2
pF
REFIN
Each pin, REFIN/
(REF1/REF2)
PHASE/FREQUENCY DETECTOR (PFD)
PFD Input Frequency
100
45
MHz
MHz
ns
ns
ns
Antibacklash pulse width = 1.3 ns, 2.9 ns
Antibacklash pulse width = 6.0 ns
Register 0x017[1:0] = 01b
Register 0x017[1:0] = 00b; Register 0x017[1:0] = 11b
Register 0x017[1:0] = 10b
Antibacklash Pulse Width
1.3
2.9
6.0
Rev. B | Page 4 of 64