Block 2 - lecture 6

Question 1

sampling?

Answer 1

the process of taking multiple measurements

Question 2

quantization levels?

Answer 2

the number of separate values possible for a binary number

Question 3

how to calculate the number of quantization levels?

Answer 3

2^n

eg. 2^8 for 8 bit

Question 4

resolution?

Answer 4

the percentage of the range for each level

eg. 0.4% for 8 bit

Question 5

impact of sampling rate?

Answer 5

too low means it’s not representative

might show a different frequency

Question 6

required sampling rate?

Answer 6

10th of the time period

Question 7

conversion time/settling time?

Answer 7

time for analog to digital convertors and digital to analog convertors to work

Question 8

what changes the conversion time/settling time

Answer 8

• convertor used
• number of bits
• DACs are faster than ADCs

Question 9

unipolar DAC?

Answer 9

output of 0v (0000) to Vref (1111)

Question 10

bipolar DAC?

Answer 10

output of -Vref (0000) to Vref (1111)

Question 11

units of resolution?

Answer 11

V/bit or %

Question 12

method for ADC?

Answer 12

• find input’s proportion of the reference
• if this *2>1, 1st bit =1
• take the remainder and repeat for next bit

Question 13

alternative method for ADC?

Answer 13

number=INT(Vin/Vref * 2^n)

gives the output in decimal, so convert to binary

Question 14

uncertainty calculation for binary numbers?

Answer 14

uncertainty = Vref*2^-n