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LTC6945
7
6945f
TYPICAL PERFORMANCE CHARACTERISTICS
Spurious Response
fRF = 914MHz, fREF = 10MHz,
fPFD = 250kHz, Loop BW = 7kHz
Spurious Response
fRF = 2100MHz, fREF = 10MHz,
fPFD = 1MHz, Loop BW = 40kHz
VCO Input Sensitivity
vs Frequency, Temperature
Closed-Loop Phase Noise,
fRF = 914MHz
Closed-Loop Phase Noise,
fRF = 2100MHz
FREQUENCY (GHz)
0
SENSITIVITY
(dBm)
–15
–10
4
6945 G13
–20
–25
–30
–35
1
2
3
5
0.5
4.5
1.5
2.5
3.5
5.5 6
105°C
25°C
–40°C
Spurious Response
fRF = 5725MHz, fREF = 10MHz,
fPFD = 5MHz, Loop BW = 21kHz
Supply Current vs Temperature
FREQUENCY OFFSET (MHz, IN 10kHz SEGMENTS)
–10 –3
–2
–1
0
2
13
10
–140
P
OUT
(dBm)
–120
–80
–60
–113dBc
–112dBc
–102dBc
–40
0
6945 G17
–100
–20
RBW = 1Hz
VBW = 1Hz
NOTES 7, 11
FREQUENCY OFFSET (MHz, IN 10kHz SEGMENTS)
–20 –15 –10 –5
0
10
515
20
–140
P
OUT
(dBm)
–120
–80
–60
–112dBc
–100dBc
–101dBc
–40
0
6945 G18
–100
–20
RBW = 1Hz
VBW = 1Hz
NOTES 7, 11
FREQUENCY OFFSET (MHz, IN 10kHz SEGMENTS)
–10 –0.75 –0.5 –0.25 0
0.5
0.25
0.75 10
–140
P
OUT
(dBm)
–120
–80
–60
–113dBc
–111dBc
–102dBc
–40
0
6945 G16
–100
–20
RBW = 1Hz
VBW = 1Hz
NOTES 7, 10, 11
TEMPERATURE (°C)
–40
3.3V
CURRENT
(mA)
5V
CURRENT
(mA)
83
84
85
40
60
100
6945 G19
82
81
80
–20
0
20
80
86
87
88
33.0
33.5
34.0
32.5
32.0
31.5
34.5
35.0
35.5
PDREFO = 1
O = 1
RFO = 3
MUTE = 0
ICP = 11.2mA
OFFSET FREQUENCY (Hz)
–150
PHASE,
NOISE
(dBc/Hz)
–140
–120
–100
–90
100
10k
100k
6945 G14
–160
1k
1M
10M 40M
–110
–130
–170
RMS NOISE = 0.13°
fPFD = 250kHz
BW = 7kHz
NOTES 7, 10
VCO = CRYSTEK
CVCO55CL-0902-0928
OFFSET FREQUENCY (Hz)
–150
PHASE,
NOISE
(dBc/Hz)
–140
–120
–100
–90
100
10k
100k
6945 G15
–160
1k
1M
10M 40M
–110
–130
–170
RMS NOISE = 0.33°
fPFD = 1MHz
BW = 40kHz
NOTE 7
VCO = RFMD
UMX-586-D16-G