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What is meant by D-FF

It is a storing device.It stores only one bit at a

time.It's output is same as the input.

The difference between a latch and a flip-flop is that a latch is asynchronous, and the

outputs can change as soon as the inputs do (or at least after a small propagation delay). A flip-

flop, on the other hand, is edge-triggered and only changes state when a control signal goes

from high to low or low to high.

In electronics, a multiplexer  (or mux) is a device that selects one of several analog or  digital input

signals and forwards the selected input into a single line.!" A multiple#er of $n inputs has n select

lines, which are used to select which input line to send to the output.$"

 %ultiple#ers are mainly usedto increase the amount of data that can be sent over the networ& within a certain amount of time

and bandwidth.!" A multiple#er is also called a data selector .

SR Flip Flop to JK Flip Flop

As told earlier, J and K will be given as external inputs to S and R. As shown in the logic diagram

below, S and R will be the outputs of the combinational circuit.

The truth tables for the ip op conversion are given below. The present state is represented b

!p and !p"# is the next state to be obtained when the J and K inputs are applied.

$or two inputs J and K, there will be eight possible combinations. $or each combination of J, K

and !p, the corresponding !p"# states are found. !p"# simpl suggests the future values to

be obtained b the JK ip op after the value of !p. The table is then completed b writing the

values of S and R re%uired to get each !p"# from the corresponding !p. That is, the values of S

and R that are re%uired to change the state of the ip op from !p to !p"# are written.

A A*+ *ITI* *+ /0/ 1*T0 T0 I2+T A 0I30

 A T0 *+T2+T T0+ +3* A TAITI* TAT.4* 5A%26

*I T0 I2+T 7A6+ I A 89 46I2 46*2:ie:8;9;! ,T0

*+T2+T <=;= I *%A6 A /I66 0A3 T* ! A 7I 7A.

T0 %> 4* A A*+ 2*16% A 1 6I%IAT 1>

+I3 A %AT 6A7 8-9 46I2 46*2'.

?ener diode is used as a voltage regulatory device..

because..

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the voltage across the ?ener diode in reverse bias is

constant after reaching certain value i.e. brea&down

voltage.

normal diodes distorts at htis brea&down voltage but the

?ener still runs after this voltage and &eeps the voltage

across the diode constant even the supply voltage increses..

in my view an ideal voltage souce means which is having

constant voltage irrespect of the current and having ?ero

internal resistance which is in series with the voltage

source

@ener brea&down and Avalanche brea&down both are under 

reverse bias.which are responsible for such large reverse

current.

 Avalanche-It ta&es place due to the drift of thermally

generated minority carriers through the Bunction under the

influence of e#ternal field.@ener brea&down-It ta&es place due to presence of strong

electric field and presence of large reverse bias voltage

• Sampling Theorem: “A bandlimited signal can be reconstructed exactly if it is

sampled at a rate atleast twice the maximum frequency component in it.”

In signal processing, the impulse response, or impulse response function (IRF), of a dynamic

system is its output when presented with a brief input signal, called an impulse. %ore generally, an

impulse response refers to the reaction of any dynamic system in response to some e#ternalchange. In both cases, the impulse response describes the reaction of the system as a function of

time (or possibly as a function of some other independent variable that parameteri?es the dynamic

behavior of the system).

>ou have this flipped, II filters are recursive and 4I filters are non-recursive. Also 4I

filters are linear phase and II filters are not: several applications are sensitive to non-linear 

phase (communications, medical, etc). In implementation, II filters reCuire fewer taps

(smaller order) and thusly are easier to implement and have fewer ?eros. Also 4I filters are

always stable, while II filters can often become unstable in implementation. The previous

answer is correct about delays.

%(common mode

reBection ratio) is the ratio of

differential mode gain to the

common mode gain. Actually

in differential amplifier it

should amplify the difference

of the two input signals and

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$When transmitting digital signals is it necessary to transmit some harmonics in addition to

fundamental fre%uenc

>es, A one freCuency signal may not be sufficient, since the

analog and digital signals may loo& different and the

receiver may not recogni?e it correctly. To improve the

shape of the signal for better communication, particularlyfor high data rates, we need to add some harmonics

For asynchronous transmission& is it necessary to supply some synchroni'ing pulses additionally or to

supply or to supply start and stop bit

asynchronous transmission does not reCuired any

syncroni?ing pulses , instead it needs start and stop bit

to ac&nowledge the first and last bit of the data which is

transmitted.these bits can be high or low.

In some advanced controllers which has in built +AT ,

provide option to select no. of start and stop bits in the

transmission.

$FS) is more efficient than FS) in presence of noise$ Why

since in bfs& only audio signals are transmitted and at the

rate of D== bits per second............

but in bpfs& along vith audio signals pitch is also

transmitted and at the rate of H==-== bits per second.....

for dat reason bpfs& is more efficient den bfs&....

What is meant by pre-emphasis and de-emphasis

2re-emphasis

J Improving the signal to noise ratio by increasing

the magnitude of higher freCuency signals with respect

to lower freCuency signalsJ

e-emphasis

J Improving the signal to noise ratio by decreasing

the magnitude of higher freCuency signals with respect

to lower freCuency signals

What do you mean by " d cutoff fre%uency? Why is it " d& not * d

That's wrong.

D d1 implies !K$ the power and since the power is

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proportional to the sCuare of voltage, the voltage will be

=,L=L of the passband voltage.

sCrt(=.G) ; =.L=L

 AII stands for American tandard ode for InformationInterchange n 1I stands for #tended 1inary oded

ecimal Interchange ode