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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

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.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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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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