LM6144BIN National Semiconductor, LM6144BIN Datasheet - Page 12

• Manufacturer Part Number: LM6144BIN
• Description: OP AMP, QUAD 17MHZ RRI/O, 6144, DIP
• Manufacturer: National Semiconductor

Specifications of LM6144BIN

• Op Amp Type: General Purpose
• No. Of Amplifiers: 4
• Bandwidth: 17MHz
• Slew Rate: 25V/µs
• Supply Voltage Range: 1.8V To 24V
• Amplifier Case Style: DIP
• No. Of Pins: 14
• Operating Temperature Range: -40°C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

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LM6142/LM6144 Application Ideas
These features allow the LM6142 to drive capacitive loads
as large as 1000pF at unity gain and not oscillate. The scope
photos (Figure 3 and Figure 4) above show the LM6142
driving a l000pF load. In Figure 3, the upper trace is with no
capacitive load and the lower trace is with a 1000pF load.
Here we are operating on
pulse. Excellent response is obtained with a C
Figure 4, the supplies have been reduced to
pulse is 4 V
compensation capacitor is best established after the board
layout is finished because the value is dependent on board
stray capacity, the value of the feedback resistor, the closed
loop gain and, to some extent, the supply voltage.
Another effect that is common to all op amps is the phase
shift caused by the feedback resistor and the input capaci-
tance. This phase shift also reduces phase margin. This
effect is taken care of at the same time as the effect of the
capacitive load when the capacitor is placed across the
feedback resistor.
The circuit shown in Figure 5 was used for these scope
photos.
(Continued)
PP
and C
f
FIGURE 2.
FIGURE 3.
is 39pF. The best value for the
±
12V supplies with a 20 V
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f
±
of l0pF. In
2.5V, the
PP
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12
Typical Applications
FISH FINDER/ DEPTH SOUNDER.
The LM6142/LM6144 is an excellent choice for battery op-
erated fish finders. The low supply current, high gain-
bandwidth and full rail to rail output swing of the LM6142
provides an ideal combination for use in this and similar
applications.
ANALOG TO DIGITAL CONVERTER BUFFER
The high capacitive load driving ability, rail-to-rail input and
output range with the excellent CMR of 82 dB, make the
LM6142/LM6144 a good choice for buffering the inputs of A
to D converters.
3 OP AMP INSTRUMENTATION AMP WITH
RAIL-TO-RAIL INPUT AND OUTPUT
Using the LM6144, a 3 op amp instrumentation amplifier with
rail-to-rail inputs and rail to rail output can be made. These
features make these instrumentation amplifiers ideal for
single supply systems.
Some manufacturers use a precision voltage divider array of
5 resistors to divide the common-mode voltage to get an
input range of rail-to-rail or greater. The problem with this
method is that it also divides the signal, so to even get unity
gain, the amplifier must be run at high closed loop gains.
This raises the noise and drift by the internal gain factor and
FIGURE 4.
FIGURE 5.
01205710
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