IT358 INFINITRUE TECHNOLOGY, IT358 Datasheet - Page 6

• Manufacturer Part Number: IT358
• Description: LOW POWER DUAL OPERATIONAL AMPLIFIER
• Manufacturer: INFINITRUE TECHNOLOGY

INFINTRUE TECHNOLOGY
APPLICATION HINTS
true-differential inputs, and remain in the linear mode with an input common-mode voltage
of 0V. These amplifiers operate over a wide range of power supply voltage with little
change in performance characteristics. At 25°C a mplifier operation is possible down to a
minimu m supply voltage of 2.3 V.
never becomes reversed in polarity or that the unit is not inadvertently installed backwards
in a test socket as an unlimited current surge through the resulting forward diode within the
IC could cause fusing of the internal conductors and result in a destroyed unit.
voltage protection diodes are not needed, no large input currents result from large
differential input voltages. The differential input voltage may be larger than V
damaging th e device. Protection should be provided to prevent th e inpu t voltages fro m
going negative more than -0.3V (at 25°C). An input clamp diode with a resistor to the IC
input termi nal can be used.
small signal levels which converts to class B in a large signal mode. This allows the
a mplifiers to both source and sink large outpu t cu rrents. Therefore both NPN and PNP
external current boost transistors can be used to extend the power capability of the basic
amplifiers. The ou tput voltage need s to raise approx imately 1 diode drop ab ov e ground to
bias th e on -chip vertical PNP transistor for ou tput cu rrent sink ing applications.
a resistor should be used, fro m the output of the amplifier to ground to increase the class A
bias cu rrent and preven t crossover distortion. Where the load is directly coupled, as in dc
applications, there is no crossover distortion.
stability margin. Values of 50pF can be accomodated using the worst-case non-inverting
unity gain connection. Large closed loop gains or resistive isolation should be used if larger
load capacitance mu st be driv en by the amplifier.
time duration. Units can be destroyed, not as a result of the short circuit current causing
metal fusing, but rath er due to th e large in crease in IC ch ip dissipation which will cause
eventual failure due to excessive function temp eratures. Putting direct short-circuits on
mo re than one amplifier at a ti me will increase the total IC power dissipation to destructive
levels, if not properly protected with ex ternal dissipation li miting resistors in series with
the output leads of the a mplifiers. The larger value of output source current which is
available at 25°C provides a larger output current capability at elevated temperatures (see
typical performance characteristics) than a standard IC op amp.
The IT358 is op amps which operate with only a single power supply voltage, have
Precautions should be taken to insure that th e power supply for the integrated circuit
Large differential input voltages can be easily acco mmo dated and, as input differential
To reduce the power supply current drain, the amplifiers have a class A output stage for
For ac applications, wh ere the load is capacitively coupled to the output of th e amplifier,
Capacitive loads which are applied directly to the output of the amplifier reduce the loop
Output short circuits either to ground or to the positive power supply should be of short
+
without
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