(A) An A/D conversion circuit with 10 bit resolution has an input range of 0 5 V. A second has a 12 bit resolution and an input range of 0 10 V. Calculate the digital output value that will represent a 2 V input for both of the A/D converters. Convert the digital levels in both cases to hexadecimal and then to binary values.

(b) Explain briefly from what you notice about the digital output values in (a) why a digital output value of an A/D converter is rarely the exact same digital value as the analogue input value.

(c) State briefly why a PLC A/D module haveing 4 analogue input channels would probably not incorporate 4 internal A/D circuits.

(d) State briefly which of the two digital output values in (a) is the more accurate and why.