30-08-2014, 02:05 PM
tecnical report
[attachment=67447]
ABSTRACT
The operational amplifier is arguably the most useful single device in analog electronic circuitry. With only a handful of external components, it can be made to perform a wide variety of analog signal processing tasks. It is also quite affordable, most general-purpose amplifiers selling for under a dollar apiece. Modern designs have been engineered with durability in mind as well: several "op-amps" are manufactured that can sustain direct short-circuits on their outputs without damage.
One key to the usefulness of these little circuits is in the engineering principle of feedback, particularly negative feedback, which constitutes the foundation of almost all automatic control processes. The principles presented here in operational amplifier circuits, therefore, extend well beyond the immediate scope of electronics. It is well worth the electronics student's time to learn these principles and learn them well.
INTRODUCTION
What exactly is an OPerational AMPlifier? Let's define what that component is and look at the parameters of this amazing device. An operational amplifier IC is a solid-state integrated circuit that uses external feedback to control its functions. It is one of the most versatile devices in all of electronics. The term 'op-amp' was originally used to describe a chain of high performance dc amplifiers that was used as a basis for the analog type computers of long ago. The very high gain op-amp IC's our days uses external feedback networks to control responses. The op-amp without any external devices is called 'open-loop' mode, referring actually to the so-called 'ideal' operational amplifier with infinite open-loop gain, input resistance, bandwidth and a zero output resistance. However, in practice no op-amp can meet these ideal
characteristics. And as you will see, a little later on, there is no such thing as an ideal op-amp. Since the LM741/NE741/uA741 Op-Amps are the most popular one, this tutorial is direct associated with this particular type. Nowadays the IC- 741 is a frequency compensated device and although still widely used, the Bi-polar types are low-noise and replacing the old-style op-amps.
DEFINITION OF OPERATIONAL AMPLIFIER:
an operational amplifier is a direct-coupled high-gain amplifier usually consisting of one or more differential amplifiers and usually followed by a level translator and an output stage. an operational amplifier is available as a single integrated circuit package. operational amplifier is available in 8pin dip package.
1 INVERTING AMPLIFIER:
The following diagram of an INVERTING AMPLIFIER. This means that if the voltage going into the 741 chip is positive, it is negative when it comes out of the 741. In other words it reverses polarity (inverts polarity).Two resistors are needed to make the 741 work as an amplifier, R1 and R2. In most text books diagrams like this are used to represent the 741.
. CHANNEL SEPARATION
Whenever there is more than one op-amp in a single package, like the 747 op-amp, a certain amount of "crosstalk" will be present. that is, a signal applied to the input of one section of a dual op-amp will produce a finite output signal in the remaining section, even though there is no input signal applied to the unused section.
7.THE INSTRUMENTATION AMPLIFIER
There are many types of op-amps who are designed for a specific purpose like the
Instrumentation Amplifier from Burr-Brown (fig 10). It can be used in both balanced and unbalanced systems, like a Wheatstone Bridge circuit. This does not mean in any way that the instrumentation amp cannot be used for other applications, on the contrary, it is in many a case preferred because of the unique parameters of this device.
SUBTRACTOR:
The Subtractor also called a difference amplifier, uses both the inverting and non-inverting inputs to produce an output signal which is proportional to the difference between the two input voltages V1 and V2. More inputs can be subtracted.Resistances are equal (R = R and RA = RA) then the output voltage is as given and the gain is +1. If the input resistance are unequal the circuit becomes a differential amplifier.
CONCLUSION
Operational amplifier (IC741) description was studied.By the use of op-amp various mathematical operations like differentiator,integrator,subtractor are studied.
[attachment=67447]
ABSTRACT
The operational amplifier is arguably the most useful single device in analog electronic circuitry. With only a handful of external components, it can be made to perform a wide variety of analog signal processing tasks. It is also quite affordable, most general-purpose amplifiers selling for under a dollar apiece. Modern designs have been engineered with durability in mind as well: several "op-amps" are manufactured that can sustain direct short-circuits on their outputs without damage.
One key to the usefulness of these little circuits is in the engineering principle of feedback, particularly negative feedback, which constitutes the foundation of almost all automatic control processes. The principles presented here in operational amplifier circuits, therefore, extend well beyond the immediate scope of electronics. It is well worth the electronics student's time to learn these principles and learn them well.
INTRODUCTION
What exactly is an OPerational AMPlifier? Let's define what that component is and look at the parameters of this amazing device. An operational amplifier IC is a solid-state integrated circuit that uses external feedback to control its functions. It is one of the most versatile devices in all of electronics. The term 'op-amp' was originally used to describe a chain of high performance dc amplifiers that was used as a basis for the analog type computers of long ago. The very high gain op-amp IC's our days uses external feedback networks to control responses. The op-amp without any external devices is called 'open-loop' mode, referring actually to the so-called 'ideal' operational amplifier with infinite open-loop gain, input resistance, bandwidth and a zero output resistance. However, in practice no op-amp can meet these ideal
characteristics. And as you will see, a little later on, there is no such thing as an ideal op-amp. Since the LM741/NE741/uA741 Op-Amps are the most popular one, this tutorial is direct associated with this particular type. Nowadays the IC- 741 is a frequency compensated device and although still widely used, the Bi-polar types are low-noise and replacing the old-style op-amps.
DEFINITION OF OPERATIONAL AMPLIFIER:
an operational amplifier is a direct-coupled high-gain amplifier usually consisting of one or more differential amplifiers and usually followed by a level translator and an output stage. an operational amplifier is available as a single integrated circuit package. operational amplifier is available in 8pin dip package.
1 INVERTING AMPLIFIER:
The following diagram of an INVERTING AMPLIFIER. This means that if the voltage going into the 741 chip is positive, it is negative when it comes out of the 741. In other words it reverses polarity (inverts polarity).Two resistors are needed to make the 741 work as an amplifier, R1 and R2. In most text books diagrams like this are used to represent the 741.
. CHANNEL SEPARATION
Whenever there is more than one op-amp in a single package, like the 747 op-amp, a certain amount of "crosstalk" will be present. that is, a signal applied to the input of one section of a dual op-amp will produce a finite output signal in the remaining section, even though there is no input signal applied to the unused section.
7.THE INSTRUMENTATION AMPLIFIER
There are many types of op-amps who are designed for a specific purpose like the
Instrumentation Amplifier from Burr-Brown (fig 10). It can be used in both balanced and unbalanced systems, like a Wheatstone Bridge circuit. This does not mean in any way that the instrumentation amp cannot be used for other applications, on the contrary, it is in many a case preferred because of the unique parameters of this device.
SUBTRACTOR:
The Subtractor also called a difference amplifier, uses both the inverting and non-inverting inputs to produce an output signal which is proportional to the difference between the two input voltages V1 and V2. More inputs can be subtracted.Resistances are equal (R = R and RA = RA) then the output voltage is as given and the gain is +1. If the input resistance are unequal the circuit becomes a differential amplifier.
CONCLUSION
Operational amplifier (IC741) description was studied.By the use of op-amp various mathematical operations like differentiator,integrator,subtractor are studied.