Electronics and Communication Engineering - Digital Electronics - Discussion
Discussion Forum : Digital Electronics - Section 1 (Q.No. 13)
13.
The circuit in the given figure is
Answer: Option
Explanation:
Since V(I) is lower state than V(0) it is a negative logic circuit. Since diodes are in reversed parallel, it is an AND gate.
Note: In Boolean algebra it is recognized that a positive logic OR is a negative logic AND. Similarly a positive logic AND is a negative logic OR.
Discussion:
29 comments Page 1 of 3.
Shiva said:
5 years ago
Not getting, Please Explain briefly.
(2)
TARUN UPADHYAY said:
5 years ago
It is -ve because 0 volts is shown as a logic high, and 1 volt is shown by logic low.
(2)
Kanika Sharma said:
7 years ago
Please, clearly explain about positive and negative logic.
(1)
Kanika Sharma said:
7 years ago
If diodes are in series then what is the answer?
(1)
Vicky said:
7 years ago
The actual configuration is for Positive logic (i,e logic 1= Vr and logic 0 = 0) AND gate, BUT since the logic has been changed to negative logic (i, e logic 1= 0, and logic 0= Vr), so instead of AND gate it will be OR gate. So, it is a Negative Logic OR gate.
(4)
Priyadarshini said:
7 years ago
How OR gate? anyone explain me clearly.
(1)
Ramya said:
7 years ago
This is negative logic or gate.
Badhshah said:
8 years ago
That is the diodes are connected in the reverse direction that is for 0 it is ON for diode it is forward biased when negative pulse is applied.
(1)
Badhshah said:
8 years ago
But if the single diode is forward biased then we are getting the output.
i.e. It's an OR gate and the input is a negative(0).
We know that for OR gate if one input is 1 then the output is 1.
So, the answer is -ve logic OR gate.
i.e. It's an OR gate and the input is a negative(0).
We know that for OR gate if one input is 1 then the output is 1.
So, the answer is -ve logic OR gate.
Nabanita said:
8 years ago
It is neg logic or gate as the diode is reverse biased it follows the following table:
0 0 = 0 (as the current flows to both of the diode the v0 output is zero)
0 1 = 0
1 0 = 0
1 1 = 1
it is pos logic and gate.
so it is neg logic or.
0 0 = 0 (as the current flows to both of the diode the v0 output is zero)
0 1 = 0
1 0 = 0
1 1 = 1
it is pos logic and gate.
so it is neg logic or.
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