Hello friends,
I am in need of a simple 2 4-bit adder in which the output shud be added with the input.
That is, it shud be capable of storing the output and use the same for the next add operation.And I shud supply only 1 4-bit as input.....

 

Hello,

On this page of the EDUCYPEDIA you will find adder circuits in the links:
http://www.educypedia.be/electronics/digitaarithmetic.htm

There are more digital related pages over there:

Digital electronics:
Arithmetic circuits D/A-A/D converters Number systems Codes and decoders Flip flops Technology Counters and registers General overview Technology-CMOS Digital logic Memories Technology-TTL Timers and oscillators


Greetings,
Bertus

 

Yes friend,I too looked over there and I was failed.I could not find the same which i need....

I need a Adder where I shud give only one input.......And it shud be added with the previous value of the adder.And it shud work only once after a clock pulse...

 

Hello,

That is why I gave you the other pages too.
You will need a register (memory) for the "old" value.
That is connected to the second value input of the adder.

Greetings,
Bertus

 

Hello friend,I triend the adder circuit with the Shift register 74LS195N.But when i gave the clock pulse for the first time (3 as my input) it is working.But for the second clock pulse I could not get the 6 as output.But I am getting 1 and in third clock pulse I am getting 2 and then 0.

Help with the circuit.....

 

Hello,

What are you using as an adder?
Take a look at the 74283 as adder.
The 74195 can be the resgister.

Greetings,
Bertus

 

Hello friend I have designed with the same you have listed and I am still facing the above said error in previous post..Pls help me to get rid off this

 

Hello,

You have turned the bits around on the adder.
Bit 1 => A (value 1)
Bit 2 => B (value 2)
Bit 3 => C (value 4)
Bit 4 => D (value 8)

Greetings,
Bertus

 

But friend when I worked the same on the Multisim I got the output as 3 correct for the first time of the clock pulse........

 

Hello,

What did you do with the carry in connection?
I would connect that to logic 0.

Greetings,
Bertus

 

But friend,even doing all the things i could not get the exact circuit functioning in the right way.....pls help to sort out off this simple circuit.