Q1.
a) A/D conversion circuit with 10 bit resolution consists of an input range of 0 – 5 V. A second has a 12-bit resolution and an input range of 0 – 10 V. Compute the digital output value which will represent a 2 V input for both of A/D converters. Transform the digital levels in both cases to hexadecimal and then to the binary values.
b) Describe in brief from what you notice regarding the digital output values in (a) why a digital output value of an A/D converter is seldom the exact same digital value as analogue input value.
c) State in brief why a PLC A/D module having 4 analogue input channels would most likely not incorporate 4 internal A/D circuits.
d) State in brief which of the two digital output values in (a) is more accurate and describe why.
Q2. Describe in brief the method of multiplexed switching of the analogue signals.