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CA3240 Dual Operational Amplifier

The CA3240 is a dual version of the popular CA3140 series integrated circuit operational amplifiers. CD3240 combines the advantages of MOS and bipolar transistors on the same monolithic chip. The gate-protected MOSFET input transistors provide high input impedance and a wide common-mode input voltage range (typically to 0.5V below the negative supply rail).


CA3240 Pin Configuration

Pin Number

Pin Name




The output pin of the Op-amp A


Inverting Input (A)

The Inverting input pin of the Op-Amp A


Non- Inverting Input (A)

The Non - Inverting Input Pin of Amplifier A


Power (-Vs)

Negative supply terminal 



The Non - Inverting Input Pin of Amplifier B



The Inverting input pin of the Op-Amp B


Power (+Vs)

The output pin of the Op-amp B



Positive supply terminal


Features and Specifications of CA3240

  • Number of Channels:2 Channel
  • Can work from a single power supply
  • GBP - Gain Bandwidth Product: 4.5 MHz
  • Supply Voltage - Max: 36 V
  • Supply Voltage - Min: 4 V
  • Maximum Dual Supply Voltage: +/- 18 V
  • Minimum Dual Supply Voltage: +/- 2 V
  • Operating Supply Current: 8 mA
  • Output Current per Channel: 40 mA
  • SR - Slew Rate: 9 V/us
  • CMRR - Common Mode Rejection Ratio: 70 dB
  • Vos - Input Offset Voltage:15 mV


Note:  Complete Technical Details can be found at the CA3240 datasheet given at the end of this page.


Similar Op-Amp. ICs

LM158, LM158A, LM358, LM358A, LM2904, LM2904Q, LM4558, LM747


Where to Use CA3240 Op Amp

CA3240 IC can be used to realize general-purpose op-amp operation circuits like comparator, differential amplification or mathematical operations. Moreover, the device specifically designed for applications like transducer amplifiers, dc amplification blocks to be implemented more easily in single-supply-voltage systems. For example, these devices can be operated directly from the standard 5V supply used in digital electronics without additional -5V supply.

In addition with two of those op-amps on board, the device can perform two different functions at a time that comes in handy in applications. The device is popular among hobbyists and engineers for being low cost and good performance.


How to Use CA3240 Op Amp IC

As mentioned above CA3240 is a dual op-amp IC. The internal connection diagram of CA3240 is shown below.

CA3240 Internal Circuit


Now let us take a single op-amp from the two and construct a simple application circuit as shown below.

Op-Amp Application Circuit

In the above circuit, the op-amp acts as a Non-Inverting Amplifier (Since the input is given to the Non-inverting terminal of the op-amp) and output is provided as Vo. Also, the device is powered from a single voltage source of VCC.

We have the equation for the output Vo =Input voltage * Gain = Vi * A = Vi * (1+R1/R2)

For example:

Say R1 = 100, R2 = 10 and Input voltage Vi = 20mV

We will have Vo = 20m*(1+10)=220mV

With that, we have realized the amplifier circuit of the op-amp and in a similar way, we use the device to design all other application circuits of an op-amp.



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  • Instrumentation  Amplifiers
Component Datasheet

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