Application Hints

The LP324 series is a micro-power pin-for-pin equivalent to

the LM324 op amps. Power supply current, input bias cur-

rent, and input offset current have all been reduced by a fac-

tor of 10 over the LM324. Like its predecessor, the LP324 se-

ries

op

amps

can

operate

on

single

supply,

have

true-differential inputs, and remain in the linear mode with an

input common-mode voltage of 0 V

The pinouts of the package have been designed to simplify

PC board layouts. Inverting inputs are adjacent to outputs for

all of the amplifiers and the outputs have also been placed at

the corners of the package (pins 1, 7, 8, and 14).

Precautions should be taken to insure that the power supply

for the integrated circuit never becomes reversed in polarity

or the unit is not inadvertently installed backwards in the test

socket as an unlimited current surge through the resulting

forward diode within the IC could destroy the unit.

Large differential input voltages can be easily accommo-

dated and, as input differential voltage protection diodes are

not needed, no large input currents result from large differen-

tial input voltages. The differential input voltage may be

larger than V

+

without damaging the device. Protection

should be provided to prevent the input voltages from going

negative more than −0.3 V

with a resistor to the IC input terminal can be used.

Voltage Follower

Pulse Response

DS008562-27

Voltage Follower Pulse

Response (Small Signal)

DS008562-28

Common Mode

Rejection Ratio

DS008562-29

Large Signal

Frequency Response

DS008562-30

Output Characteristics

Current Sourcing

DS008562-31

Output Characteristics

Current Sinking

DS008562-32

Current Limiting

DS008562-33

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