LTC6945
3
6945f
ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TC = 25°C. VREF+ = VREF0+ = VD+ = VRF+ = VVCO+ = 3.3V, VCP+ = 5V unless otherwise
specified. All voltages are with respect to GND.
SYMBOL
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
Reference Output (REFO)
fREFO
Output Frequency
l
10
250
MHz
PREFO
Output Power
fREFO = 10MHz, RLOAD = 50Ω
l
–0.2
3.2
dBm
Output Impedance, Disabled
800
Ω
VCO Input (VCO+, VCO–)
fVCO
Input Frequency
l
350
6000
MHz
PVCOI
Input Power Level
RZ = 50Ω, Single-Ended
l
–8
0
6
dBm
Input Resistance
Single-Ended, Each Input
l
97
121
145
Ω
RF Output (RF+, RF–)
fRF
Output Frequency
l
350
6000
MHz
O
Output Divider Range
All Integers Included
l
16
Output Duty Cycle
50
%
Output Resistance
Single-Ended, Each Output to VRF+
l
111
136
159
Ω
Output Common Mode Voltage
l
2.4
VRF+
V
PRF(SE)
Output Power, Single-Ended,
fRF = 900MHz
RFO[1:0] = 0, RZ = 50Ω, LC Match
RFO[1:0] = 1, RZ = 50Ω, LC Match
RFO[1:0] = 2, RZ = 50Ω, LC Match
RFO[1:0] = 3, RZ = 50Ω, LC Match
l
–9.7
–6.8
–3.9
–1.2
–6.0
–3.6
–0.4
2.3
dBm
Output Power, Muted
RZ = 50Ω, Single-Ended, fRF = 900MHz, O = 2 to 6 l
–60
dBm
Mute Enable Time
l
110
ns
Mute Disable Time
l
170
ns
Phase/Frequency Detector
fPFD
Input Frequency
l
100
MHz
Lock Indicator, Available on the STAT Pin and via the SPI-Accessible Status Register
tLWW
Lock Window Width
LKWIN[1:0] = 0
LKWIN[1:0] = 1
LKWIN[1:0] = 2
LKWIN[1:0] = 3
3.0
10.0
30.0
90.0
ns
tLWHYS
Lock Window Hysteresis
Increase in tLWW Moving from Locked State to
Unlocked State
22
%
Charge Pump
ICP
Output Current Range
12 Settings (See Table 5)
0.25
11.2
mA
Output Current Source/Sink Accuracy
VCP = VCP+/2, All Settings
±6
%
Output Current Source/Sink Matching
ICP = 250μA to 1.4mA, VCP = VCP+/2
ICP = 2mA to 11.2mA, VCP = VCP+/2
±3.5
±2
%
Output Current vs Output Voltage
Sensitivity
(Note 3)
l
0.1
0.5
%/V
Output Current vs Temperature
VCP = VCP+/2
l
170
ppm/°C
Output Hi-Z Leakage Current
ICP = 700μA, CPCLO = CPCHI = 0 (Note 3)
ICP = 11.2mA, CPCLO = CPCHI = 0 (Note 3)
0.5
5
nA
VCLMP(LO)
Low Clamp Voltage
CPCLO = 1
0.84
V
VCLMP(HI)
High Clamp Voltage
CPCHI = 1, Referred to VCP+
–0.96
V
VMID
Mid-Supply Output Bias Ratio
Referred to (VCP+ – GND)
0.48
V/V