Is Multiplier an Analog device or Digital device?

[pavan garate]

Suppose, a 4-bit x 4-bit array multiplier has been designed using the AND gates and Adders. My question is- Whether that multiplier is analog device or digital device?
Since the transistors are used to design that multiplier, it must be an analog device. But the inputs and outputs of that multiplier are digital (in bits). So, whether it's analog or digital device? What could be the applications of that multiplier?

 

[adi0803199]

The classification whether the multiplier is of analog or digital in nature is dependent upon the input and the output that we get out of the instrument.In your case,it is an digital multiplier as it takes two input signals from the channel to be of digital form.The output you get is the multiplied result which is also in digital form so it is a digital multiplier.You need to realize that even digital components are also made of transistors only(FET acting as a switch).

 

[pavan garate]

Thank you.
What could be the possible applications of such digital multiplier (e.g. filter, amplifier, etc) ?

 

[adi0803199]

These type of digital signals are used in several DSP application for the designing of filters which are used in signal processing applications.There are some microprocessors that have inbuilt registers that perform Digital multiplication two binary numbers.Suppose you write a code in High level language say C#

int a,b,res;
res=a*b;

The compiler can execute the function either by direct multiplication of two binary digits or by adding the number a with itself for b times yielding the same result.(i.e. a*b).How the code is going to be implemented is dependent on the hardware present in the microcontroller chip present that executes the code written.

 

[pavan garate]

I don't want to design the multiplier & filter using VHDL, Verilog, MATLAB or any other coding language. I want to design them using the MOSFETs in ASIC. What are your suggestions?
Which filters are commonly used for signal & image processing applications?
Which tools are better for simulation? Is any of them available free of cost on net?