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

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.