Question

Draw circuit diagram for AND gate using diodes and resistors.

Answer 1

a). A=0,B=0
both diodes are in forward bias condition and they conduct and hence the output will be zero, because the supply voltage V will be dropped across R only. Therefore Y = 0.
b) A=0,B=1
diode D1 is forward biased
D2 is reverse biased
The diode D1 will now conduct due to forward biasing
Y = 0
c)A=1,B=0
diode D2 will be conducting
Y = 0
d)A=1,B=1
both the diodes are not conducting
Y=1