![](http://datasheet.mmic.net.cn/Linear-Technology/LTC1749IFW-PBF_datasheet_101514/LTC1749IFW-PBF_7.png)
7
LTC1749
1749f
TYPICAL PERFOR A CE CHARACTERISTICS
UW
8192 Point FFT, fIN = 250.2MHz,
–10dB, PGA = 1
8192 Point FFT, fIN = 250.2MHz,
–20dB, PGA = 1
8192 Point 2-Tone FFT, 25.01MHz
and 30.1MHz, –7dB, PGA = 0
SFDR vs 30.2MHz Input Level,
PGA = 0
SFDR vs 140.2MHz, Input Level,
PGA = 1
FREQUENCY (MHz)
0
AMPLITUDE
(dBFS)
–60
–30
–20
40
1749 G16
–70
–80
–120
10
20
30
5
15
25
35
–100
0
–10
–40
–50
–90
–110
FREQUENCY (MHz)
0
AMPLITUDE
(dBFS)
–60
–30
–20
40
1749 G17
–70
–80
–120
10
20
30
5
15
25
35
–100
0
–10
–40
–50
–90
–110
FREQUENCY (MHz)
0
AMPLITUDE
(dBFS)
–60
–30
–20
40
1749 G18
–70
–80
–120
10
20
30
5
15
25
35
–100
0
–10
–40
–50
–90
–110
8192 Point 2-Tone FFT, 65.01MHz
and 70.01MHz, –7dB, PGA = 0
FREQUENCY (MHz)
0
AMPLITUDE
(dBFS)
–60
–30
–20
40
1749 G19
–70
–80
–120
10
20
30
5
15
25
35
–100
0
–10
–40
–50
–90
–110
INPUT LEVEL (dBFS)
–80
0
SFDR
(dBc
AND
dBFS)
20
40
60
80
–70 –60 –50 –40
1749 G20
–30
0
100
10
30
50
70
90
110
–20 –10
SFDR vs 70.2MHz, Input Level,
PGA = 0
INPUT LEVEL (dBFS)
–80
0
SFDR
(dBc
AND
dBFS)
20
40
60
80
–70 –60 –50 –40
1749G21
–30
0
100
10
30
50
70
90
110
–20 –10
INPUT LEVEL (dBFS)
–80
0
SFDR
(dBc
AND
dBFS)
20
40
60
80
–60
–40
–20
0
1749 G22
100
120
–70
–50
–30
–10
SFDR vs 250.2MHz, Input Level
SNR vs Input Frequency and
Amplitude, PGA = 0
INPUT LEVEL (dBFS)
–80
0
SFDR
(dBc
AND
dBFS)
20
40
60
80
–60
–40
–20
0
1749 G23
100
120
–70
–50
–30
–10
INPUT FREQUENCY (MHz)
0
SNR
(dBFS)
69.5
70.0
70.5
150
250
1749 G24
69.0
68.5
68.0
50
100
200
71.0
71.5
72.0
300
–1dB
–10dB
–20dB