LM7301
http://onsemi.com
11
APPLICATIONS INFORMATION
GENERAL INFORMATION
The LM7301 is ideal in a variety of situations due to low
supply current, wide bandwidth, wide input common mode
range extending 100 mV beyond the rails, full rail-to-rail
output, high capacitive load driving ability, wide supply
voltage (1.8 V to 32 V), and low distortion. The high
common mode rejection ratio and full rail-to-rail input range
provides precision performance, particularly in non−
inverting applications where the common mode error is
added directly to the other system errors.
CAPACITIVE LOAD DRIVING
The LM7301 is capable of driving large capacitive loads.
A 1000 pF load only reduces the phase margin to about 25°.
WIDE SUPPLY RANGE
High PSRR and CMRR provide precision performance
when the LM7301 is operating on a battery or other
unregulated supplies. This advantage is further enhanced by
the very wide supply range of 1.8 V to 32 V. In situations
where highly variable or unregulated supplies are present,
the excellent PSRR and wide supply range will maintain this
precision performance, even in such adverse supply
conditions.
SPECIFIC ADVANTAGES OF 5−Pin TSOP
The most apparent advantage of the 5−pin TSOP is that it
can save board space, a critical aspect of any portable or
miniaturized system design. The need to decrease the overall
system size is inherent in any portable or lightweight system
application. Furthermore, the low profile can help in height
limited designs, such as consumer hand−held remote
controls, sub−notebook computers, and PCMCIA cards.
An additional advantage of the tiny TSOP-5 package is
that it allows better system performance due to ease of
package placement. Because the package is so small, it can
fit on the board right where the op amp needs to be placed
for optimal performance, unconstrained by the usual space
limitations. This optimal placement allows for many system
enhancements, which cannot be easily achieved with the
constraints of a larger package. For example, problems such
as system noise due picking up undesired digital signal can
be easily reduced or mitigated. This pick−up problem is
often caused by long wires in the board layout going to or
from an op amp. By placing the tiny package closer to the
signal source and allowing the LM7301 output to drive the
long wire, the signal becomes less sensitive to such noise.
An overall reduction of system noise results.
Often, trying to save space by using dual or quad op amps
causes complicated board layouts due to the requirement of
routing several signals to and from the same place on the
board. Using the tiny op amp eliminates this problem.
LOW DISTORTION, HIGH OUTPUT DRIVE CAPABILITY
The LM7301 offers excellent low distortion performance,
with a THD+N of 0.02% at f = 10 kHz. Low distortion levels
are offered even at in scenarios with high output current and
low load resistance.
TYPICAL APPLICATIONS
HANDHELD REMOTE CONTROLS
The LM7301 offers outstanding specifications for
applications requiring balance between speed and power. In
applications such as remote control operation, where high
bandwidth and low power consumption are needed, the
LM7301 performance can easily meet these requirements.
OPTICAL LINE ISOLATION FOR MODEMS
The combination of low distortion and high load driving
capabilities of the LM7301 make it an excellent choice in
modems for driving opto-isolator circuits to achieve line
isolation. This technique prevents telephone line noise from
coupling onto the modem signal. Superior isolation is
achieved by coupling the signal optically from the computer
modem to the telephone lines; however, this also requires a
low distortion at relatively high currents. Due to its low
distortion at high output drive currents, the LM7301 fulfills
this need, in this as well as other telecom applications.
REMOTE MICROPHONE IN PERSONAL COMPUTERS
Remote microphones in computers often utilize a
microphone at the top of the monitor, which requires driving
a long cable in a high noise environment. One method often
used to reduce the noise is to lower the signal impedance to
reduce the noise pickup. In this configuration, the amplifier
usually requires 30 db to 40 db of gain, at bandwidths higher
than most low−power CMOS parts can achieve. The
LM7301 offers the tiny package, higher bandwidth, and
large output drive capability necessary for this application.
ORDERING INFORMATION
Device Marking Package Shipping
†
LM7301SN1T1G JFG SOT23−5
(Pb−Free)
3000 / Tape & Reel
†For information on tape and reel specifications, including part orientation and tape sizes, please refer to our Tape and Reel Packaging
Specifications Brochure, BRD8011/D.
