CLC5665IN National Semiconductor, CLC5665IN Datasheet - Page 8

• Manufacturer Part Number: CLC5665IN
• Description: IC AMP LOW DISTORTION 8-DIP
• Manufacturer: National Semiconductor

Specifications of CLC5665IN

• Amplifier Type: Current Feedback
• Number Of Circuits: 1
• Slew Rate: 1800 V/µs
• -3db Bandwidth: 90MHz
• Current - Input Bias: 3µA
• Voltage - Input Offset: 15000µV
• Current - Supply: 11mA
• Current - Output / Channel: 85mA
• Voltage - Supply, Single/dual (±): 10 V ~ 30 V, ±5 V ~ 15 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Through Hole
• Package / Case: 8-DIP (0.300", 7.62mm)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Output Type: -
• Gain Bandwidth Product: -
• Other names: *CLC5665IN

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Application Division
General Design Considerations
The CLC5665 is a general purpose current-feedback ampli-
fier for use in a variety of small- and large-signal applica-
tions. Use the feedback resistor to fine tune the gain flatness
and −3dB bandwidth for any gain setting. National provides
information for the performance at a gain of +2 for small and
large signal bandwidths. The plots show feedback resistor
values for selected gains.
Gain
Use the following equations to set the CLC5665’s non-
inverting or inverting gain:
Choose the resistor values for non-inverting or inverting gain
by the following steps.
1) Select the recommended feedback resistor R
plot in the plot section entitled R
2) Choose the value of R
3) Select R
4) Select R
High Gains
Current feedback closed-loop bandwidth is independent of
gain-bandwidth-product for small gain changes. For larger
gain changes the optimum feedback resister R
the following:
As gain is increased, the feedback resistor allows bandwidth
to be held constant over a wide gain range. For a more
complete explanation refer to application note OA-25 Stabil-
ity Analysis of Current-Feedback Amplifiers.
Resistors have varying parasitics that affect circuit perfor-
mance in high speed design. For best results, use leaded
metal film resistors or surface mount resistors. A SPICE
model for the CLC430 is available to simulate overall circuit
performance.
Enable/Disable Function
The CLC430 amplifier features an enable/disable function
that changes the output and inverting input from low to high
impedance. The pin 8 enable/disable logic levels are as
follows:
Non Inverting Gain
Inverting Gain
V
CC
V
R
in
f
±
FIGURE 1. Component Identification
= 724
s
in
15V
R
to set the circuit output impedance.
for input impedance and input bias.
in
±
R
- 60
-R
5V
R
g
g
f
+
CLC5665
-
· (A
g
1
R
to set gain.
f
V
)
R
R
f
vs. Gain).
g
f
R
s
DS015015-20
f
is derived by
f
V
(refer to
o
8
The amplifier is enabled with pin 8 left open due to the 2k
pull-up resistor, shown in Figure 2 .
Open-collector or CMOS interfaces are recommended to
drive pin 8. The turn on and off time depends on the speed of
the digital interface.
The equivalent output impedance when disabled is shown in
Figure 3 . With R
dominates and reduces the disabled output impedance. To
raise the output impedance in the disabled state, connect the
CLC5665 as a unity-gain voltage follower by removing R
Current-feedback op amps need the recommended R
unity-gain follower circuit. For high density circuit layouts
consider using the dual CLC431 (with disable) or the dual
CLC432 (without disable).
Enable
Disable
FIGURE 2. Pin 8 Equivalent Disable Circuit
V
Pin 8 DISABLE
in
>
2k
R
<
8k
12.7V
g
10.0V
g
connected to ground, the sum of R
+
-
300k
>
8pF
<
2.7V
0.8V
R
f
Equivalent Impedance
in Disable
+ V
- V
To CLC5665
Bias network
cc
cc
DS015015-21
DS015015-22
V
out
f
and R
f
in a
g
g
.