OPA660 Burr-Brown, OPA660 Datasheet - Page 17

• Manufacturer Part Number: OPA660
• Description: Wide Bandwidth OPERATIONAL TRANSCONDUCTANCE AMPLIFIER AND BUFFER
• Manufacturer: Burr-Brown

FIGURE 24. Frequency Response Direct-Feedback Amplifier.
FIGURE 26. Direct-Feedback Amplifier Large-Signal Pulse
FIGURE 28. Frequency Response Forward Amplifier.
–10
–15
–20
–25
–10
–15
–20
–25
–30
–30
20
15
10
–5
20
15
10
–5
5
0
5
0
100k
100k
0
R
5
5
Response.
= 100
R
R
2
1
Gain = 3, V
= 180
10
= 100
OPA660 OTA FORWARD AMPLIFIER
I
1M
1M
R
Q
15
OPA660 DIRECT FEEDBACK
6
= 20mA R
= 68
R
R
3
20
2
I
= 56
Time (ns)
= 2Vp-p, t
= 120
Frequency (Hz)
Frequency (Hz)
I
25
Q
1
= 20mA R
10M
10M
= 160
R
4p
30
R
R
3
= 75
= t
= 390
35
F
R
p
= 2ns
4
= 82
C
= 51
1.4Vp-p
0.2Vp-p
0.2Vp-p
40
0.6Vp-p
0.6Vp-p
4p
1.4Vp-p
R
2.8Vp-p
100M
100M
2.8Vp-p
= 5.6pF
4
5Vp-p
5Vp-p
= 200
45 50
C
p
= 6.4pF
+3V
0V
–3V
1G
1G
17
FIGURE 25. Direct-Feedback Amplifier Small-Signal Pulse
FIGURE 27. Forward Amplifier.
SPICE MODELS
Computer simulation using SPICE models is often useful
when analyzing the performance of analog circuits and sys-
tems. This is particularly true for video and RF amplifier
circuits, where parasitic capacitance and inductance can have
a major effect on circuit performance. SPICE models are
available from Burr-Brown.
V
I
160
0
R
1
5.6pF
Response.
75
C
R
5
Gain = 3, t
4P
3
4P
B
10
C
8
OTA
15
E
2
R
V
– t
O
20
Time (ns)
F
51
R
= 2ns, V
4
180
R
I
Q
25
2
= 20mA
OPA660
56
30
I
= 100mVp–p
100mV
300mV
700mV
35
1.4V
2.5V
V
O
R
3
40
Network
Analyzer
45 50
351MHz
374MHz
435MHz
460MHz
443MHz
f
–3dB
50
R
IN
+150mV
0V
–150mV
®