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= 0V --------------------------(6.5)

Since the resistors are more or less temperature tracked therefore ratios remain temperature independent. Hence output voltage V o does not vary with temperature. Only mismatch in the input circuit (with respect to beta, V BE , I CO ) causes a finite V o (i.e. offset voltage), and with temperature variation this mismatch gates magnified and causes a drift of V 0

In Fig 6.26 it is seen that output transistor Q 12 and Q 13 have three times cross-sectional area as that of the emitter base junction of D4. Hence output transistors carry 3 times as much current as D4. From dc bias condition,

I Q12 = I Q13 = 3(I D4 ) = 308mA;

Because of this enhanced signal handling capacity MC1530 will drive load resistors as low as 1k to a maximum p-p swing of 11 volts with Vcc = ±6 volts. Also because of high quiescent current in output stage maximum power is dissipated in Q12, Q13. Most of the dissipated energy is sunk by the header but not without heating the chip. Hence during the operation invariably a temperature gradient and a set of isothermals are set up on the chip as shown in Fig (6.28).

As can be seen in Fig.(6.28) input pairs Q 2 and Q 4 , Q 1 and Q 5 are kept on the least isothermal, farthest away from the output transistors, and in close vicinity to each other. The result is that there is least heating of the input pairs because of high output power dissipation, maximum temperature tracking of the input pairs and diffusion profiles of the input pairs very closely match to one another. Because of close proximity and the resultant diffusion profile matching, V BE and betas of the input pairs of transistors very closely match hence very low input offset voltages and currents are caused typically V os =2mV. Because of excellent temperature tracking of the input pairs, the long term drift of temperature appears mainly as common mode signal thereby minimizing the long term drift of V os to 3.8µV/ o C. Both these parameters V os and low drift are indicative of proper layout of the devices on the chip.

As can be seen in Fig.(6.27) D 1, D 2 are in close proximity to Q 3 and the three are more or less on the same isothermal, D 3 is in close proximity to Q 10 as well as the two are on same isothermal, and D 4 is in close proximity to Q 13 . Each of these are bias current sources. Because of matching of the characteristics and because of temperature tracking of the devices in the current sources, each current source is the current mirror of the reference current. And because of the use of diode configuration of the transistor which results in heavy voltage shunt feedback the reference current are highly stabilised against temperature changes. This is also known as diode compensation. Hence almost drift free near ideal current sources are achieved. Because of the stability the bias sources, the ac performance of this chip is highly stabilised. The open loop gain A d = 72dB ± 1.5dB from T = -55 o C to T= +125 o C.

The monolithic IC chip MC 1530-31 is mounted on 10 pins TO-5 packages. Two battery biases V cc ,

-V EE , output and ground leads require four pins, two pins are used for inputs and four pins are for internal connections.

Questions & Answers

Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
yes that's correct
I think
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
how nano science is used for hydrophobicity
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
what is differents between GO and RGO?
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
analytical skills graphene is prepared to kill any type viruses .
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
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Source:  OpenStax, Solid state physics and devices-the harbinger of third wave of civilization. OpenStax CNX. Sep 15, 2014 Download for free at http://legacy.cnx.org/content/col11170/1.89
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