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Introduction to Lm324n

Hey Guys! Hope you are doing great and having fun. Today, I am going to unlock the details on the Introduction to Lm324n. It is a seven pin operational amplifier that comes in discrete and compact single package. It is a high gain voltage amplifier, where output voltage signal is much higher than the input voltage signal. I'll try my best to cover as many aspects as possible related to this operational amplifier so you don't need to go any where and you find all information at one place. Let's get started. [otw_is sidebar=otw-sidebar-7]

Introduction to Lm324n

• Lm324n is a high gain voltage amplifier that comes with differential input and single ended output.
• It is designed in such a way, that the voltage difference between input terminals creates an output signal of much larger magnitude.

 

• It consists of four independent op-amp that are incorporated in a single 14 pin DIP package.
• Operational amplifiers are the initial devices that were used in analog computer to perform many mathematical operations in many nonlinear and linear circuits.
• Lm324n mostly operates on a single power supply and with wide range of voltages.
• We can also operate this device on a split power supply however, supply current drain doesn't depend on the strength of supply voltage.
• The characteristic of this circuit, its band width, impedance, and input don't effect manufacturing variations and temperature coefficient because this op-amp exhibits negative feedback.
• Op-amp are widely used in many electronic applications as oscillator, rectifier and comparators  and are most common scientific devices these days.
• Output voltage of this amplifier goes to ground and it also allows direct sensing ground. Lm324n is compatible with all forms of logic circuits.
• Power drain incorporated in this amplifier is suitable for battery operation.
• In the linear mode of operation, voltage ranges between ground and out put voltage.
• The unity gain cross frequency and input bias current of this amplifier is temperature compensated.

• Normally operational amplifiers amplifies the difference between the input voltage which is normally called the differential input voltage.
• The differential inputs of this amplifier consists of inverting input voltage with V_ and non-inverting input voltage with V+. The output of the this op-amp is given by

V(out)= AoL(V+ _ V_)

• Here AoL represents the open loop gain of the amplifier. As it is an open loop gain so it doesn't contain feedback from output to the input.
• The magnitude of AoL is very high sometimes goes to 100,000, so small difference between non-inverting and inverting voltages magnifies the output voltage to nearly supply voltage.
• A state in which output voltage is equal or greater than input supply voltage is called saturation state of the amplifier.
• It is important to note magnitude of open loop gain of the amplifier can not be controlled by the manufacturing process, so open loop amplifier can not be used as a standalone differential amplifier.
• Op-amp is behaved like a comparator in the absence of negative feedback.
• If positive voltage is applied at the non-inverting terminal and inverting terminal is set to ground with the help of resister, then the output will turn out to be maximum positive and if negative voltage is applied on the non-inverting terminal the output voltage will be maximum negative.

Lm324n Pinout

Pinout of Lm324n is shown in the figure below.

• It mainly consists of 14 pins. Function of each pin is shown in the figure below.

• Lm324n operates on a single power supply and contains true differential inputs that operate in linear mode.
• It can operate over a multiple range of power supply voltage which have little impact on performance characteristics.
• At 25 ºC, Lm324n can operate over a minimum voltage supply of 2.3V.

Absolute Maximum Rating Lm324n

Absolute maximum rating of Lm324n is shown in the figure below.  

• It is important to note that input voltage shown in the figure above will only exist when voltage at any input terminals is driven negative.
• This happens because collector base junction of PNP transistors turns to forward biased mode, which ultimately behaves as input diode clamps.
• This transistor action allows the output voltage oscillates between positive voltage supply and ground.
• It will only happen between the time duration when input is driven negative.
• Short circuits from output to the positive supply voltage can create excessive heating which ultimately damages the device.

Functional Block Diagram

Following figure shows the functinal block diagram of Lm324n.

• There is no need of diodes for differential voltage protection because large differential input voltages don't exhibit large current.
• The differential input voltage can exceed from input positive voltage without harming the device.
• However, protection must be needed in order to avoid input voltage from going too negative below than _ 0.3 V. A simple diode with resistor can be used as a protection on the input of voltage terminals.
• In order to minimum the power drain, these amplifies have Class A output stage for small signals which evidently convert to Class B out put stage for large signals.
• This action causes the amplifiers to sink and source the large current. Both, NPN and PNP resistors can be used to increase the power intensity of the basic amplifiers.
• In most of the AC application, output of the load is capacitively connected with amplifier, A resistor must be connected to the amplifier out put and ground in order to avoid crossover distortion and to enhance class A bias current.
• No cross over distortion is observed when out put load is directly connected with the amplifier.

Applications

• Lm324n is widely used in transducer amplifiers.
• DC gain blocks and conventional amplifiers circuits are mainly consists of Lm324n.
• It can be used as a rectifier, oscillator and comparator.

That's all for today. I hope you have got a clear idea about this amplifier. However, if you have any question or query regarding this amplifier, you can ping me a comment in the section below. I'll try my best to help you in this regard. Stay tuned!

Introduction to LM324

Hello everyone! I hope you all will be absolutely fine and having fun. Today, I am going to elaborate about the Introduction to LM324. It is an Operational Amplifier (Op-amp) consists of four channels. Its a low cost device having true differential inputs.For single supply applications LM 324 are superior to the other operational amplifiers. LM-324 is capable of operating at the minimum voltage up to 3V and at the high voltage levels up to 32V. One of the major advantage of LM-324 is that common mode input range includes negative supply which eliminates the need of external biasing. Negative power supply voltage is also included in output voltage range. This device is lead (Pb) free, halogen free and RoHS compliant. It consists of four amplifiers per package. LM 324 real life applications include conventional amplifier circuits, transducer amplifier, DC gain blocks etc. Further detail about LM324 e.g. its pins configuration, thermal and electrical characteristics, its features and applications will be explained in detail later in this tutorial. [otw_is sidebar=otw-sidebar-7]

Introduction to LM324

LM324 is an operational amplifier consists of four channels. It is most commonly used amplifier due to its low cost factor. It consists of four amplifiers per package and is superior to other amplifiers for single supply applications. Negative power supply included in common mode input and output range eliminates the need of external biasing. It has several different applications e.g. DC gain blocks, transducer amplifiers, conventional amplifier circuits etc. LM 324 is shown in the figure given below.

1. LM324 Pinout

• We must know the description of each pin before using any of the devices for its appropriate use.
• LM-324 has fourteen (14) pins in total having different individual functions associated with them.
• All of the fourteen pins along with their names are given in chronological order in the table shown below.

2. LM324 Configurations

• Each of the pin should be clearly labeled, if someone is going to use any device for the first time or after a long time.
• Properly labeled pinout diagram of any device results in better understanding of its functionality.
• So, I have made a completely labeled diagram for LM 324 pinout, you can see it in the figure shown below.

3. LM324 Packages

• LM-324 has four different type of packages having different individual dimensions.
• The packages include TSSOP, SOIC, CDIP and PDIP.
• ALl of the above packages are given along with their dimensions, in the table shown below.

4. LM324 Ratings

• The current, power and voltage ratings of any device indicates its power requirements i.e. the amount of current and voltage at which a particular device starts its operation properly.
• The current, voltage and power ratings of LM-324 are provided in the table shown below.

5. LM324 Schematic Diagram

• The schematic diagram of a device helps to understand its internal functionality.
• I have provided a schematic diagram of LM-324 as shown in the figure below.

• From the above figure, you can see that LM 324 consists of four amplifiers per package.
• The inputs of these amplifiers are connected to the pin number 2, 3, 5, 6, 9, 10, 12 and 13  respectively.
• The output of these amplifiers are connected to 1, 7, 8 and 14 pins.

6. LM324 Applications

There are different LM324 real life applications, a few of which are given below.

• Conventional amplifier circuits
• Transducer amplifier.
• DC gain blocks.

6. LM324 Proteus Simulation

• You should have a look at Automatic Street Light Project in Proteus, I have used LM324 in this simulation.
• I have also designed an LM324 Proteus Simulation so that you can get better idea of its working.
• I have designed a simple circuit in which LED goes ON or OFF automatically depending on LDR value.
• It's OFF state is shown in below figure:

• You can see in above figure that I have attached LDR at inputs while the LED at its output.
• Variable resistor is used for controlling the sensitivity of LDR sensor.
• It's ON state is shown in below figure:

• You can download this LM324 Proteus Simulation by clicking the below button:

Download Proteus Simulation

So that is all from the tutorial Introduction to LM324. I hope you enjoyed this exciting tutorial. If you face any sort of issues you can ask me in comments anytime you want, without even feeling any kind of hesitation. I will try my level best to solve your issues in a better way, if possible. Our team is also 24/ here to entertain you. I will explore further IC's in my upcoming tutorials and will surely shre them with you as well. So, till then take care :)