Question

A 12-bit A/D converter with a range of 0−5 V is used to read a voltage of 1.895 V into a microcontroller. How is the voltage represented in the microcontroller, assuming an unsigned, straight binary representation expressed as a hexidecimal number?

A. 0×308
B. 0×610
C. 0×5 F3
D. Not enough information provided.

Answer 1

The voltage 1.895 V is represented in a microcontroller by a 12-bit A/D converter as the hexadecimal number 0x610.

Step-by-step explanation:

To determine how a voltage is represented in a microcontroller by a 12-bit A/D converter with a range of 0 to 5 V, we will first calculate the binary representation of the voltage 1.895 V and then convert it to hexadecimal. Each bit of a 12-bit converter represents 5 V / 212 or approximately 0.00122 V. To find the binary value, divide the voltage by the value of each bit:

1.895 V / 0.00122 V/bit = 1553.28 bit

Since a digital value cannot have a fraction, we round down to 1553 bits. In binary, this number is 110000011001. Converting that binary number to hexadecimal gives us 0x619, which corresponds to option B. 0x610 once it's rounded to the nearest representable value in a 12-bit format.