Datasheet
6
LT1251/LT1256
TYPICAL PERFORMANCE CHARACTERISTICS
UW
FREQUENCY (Hz)
100k
VOLTAGE GAIN (dB)
PHASE SHIFT (DEG)
1M 10M 100M
1251/56 G13
5
4
3
2
1
0
–1
–2
–3
–4
–5
45
0
–45
–90
–135
–180
–225
–270
V
S
= ±5V
R
F
= 1.3k
R
L
= 100Ω
PHASE
GAIN
Voltage Gain and Phase
vs Frequency
Bandwidth vs Feedback
Resistance, A
V
= 1, R
L
= 1k
FEEDBACK RESISTANCE (kΩ)
0.6
–3dB BANDWIDTH (MHz)
70
60
50
40
30
20
10
0.8
1.0 1.2 1.4
1251/56 G12
1.6 1.8
PEAKING ≤ 0.5dB
PEAKING ≤ 5.0dB
V
S
= ±15V
V
S
= ±5V
V
S
= 5V
FEEDBACK RESISTANCE (kΩ)
0.6
–3dB BANDWIDTH (MHz)
70
60
50
40
30
20
10
0.8
1.0 1.2 1.4
1251/56 G11
1.6 1.8
PEAKING ≤ 0.5dB
PEAKING ≤ 5.0dB
V
S
= ±15V
V
S
= ±5V
V
S
= 5V
Bandwidth vs Feedback
Resistance, A
V
= 1, R
L
= 100Ω
Bandwidth vs Feedback
Resistance, A
V
= 10, R
L
= 100Ω
FEEDBACK RESISTANCE (kΩ)
0.4
–3dB BANDWIDTH (MHz)
60
50
40
30
20
10
0.6
0.8 1.0 1.2
1251/56 G14
1.4 1.6
PEAKING ≤ 0.5dB
PEAKING ≤ 5.0dB
V
S
= 5V
V
S
= ±15V
V
S
= ±5V
Bandwidth vs Feedback
Resistance, A
V
= 100, R
L
= 100Ω
FEEDBACK RESISTANCE (kΩ)
0.2 0.4
–3dB BANDWIDTH (MHz)
2.0
1251/56 G17
0.6 0.8
1.0 1.41.2
1.6 1.8
10
9
8
7
6
5
4
3
2
V
S
= ±15V
V
S
= 5V
V
S
= ±5V
NO PEAKING
Bandwidth vs Feedback
Resistance, A
V
= 10, R
L
= 1k
FEEDBACK RESISTANCE (kΩ)
0.4
–3dB BANDWIDTH (MHz)
60
50
40
30
20
10
0.6
0.8 1.0 1.2
1251/56 G15
1.4 1.6
PEAKING ≤ 0.5dB
PEAKING ≤ 5.0dB
V
S
= 5V
V
S
= ±15V
V
S
= ±5V
Bandwidth vs Feedback
Resistance, A
V
= 100, R
L
= 1k
FEEDBACK RESISTANCE (kΩ)
0.2 0.4
–3dB BANDWIDTH (MHz)
2.0
1251/56 G18
0.6 0.8
1.0 1.41.2
1.6 1.8
10
9
8
7
6
5
4
3
2
V
S
= ±15V
V
S
= 5V
V
S
= ±5V
NO PEAKING
FREQUENCY (Hz)
OFF-CHANNEL ISOLATION (dB)
0
–10
–20
–30
–40
–50
–60
–70
–80
–90
–100
10k 1M 10M 100M
1251/56 G16
100k
V
S
= ±5V
V
FS
= 2.5V
V
C
= 0V
R
L
= 100Ω
R
F
= 1.5k
A
V
= 10
A
V
= 1
Off-Channel Isolation
vs Frequency
–3dB Bandwidth vs
Control Voltage
CONTROL VOLTAGE (V)
0
–3dB BANDWIDTH (MHz)
40
35
30
25
20
15
10
0.5 1.0 1.5 2.0
1251/56 G19
2.5
V
S
= ±5V
R
L
= 100Ω
V
FS
= 2.5V
R
F
= 1.3k