Question

Q2. Answer the following questions a) An ADC converter is required to digitize a -5 to +5 volts analog signal to a resolution of b) The analog input is 0-5 volts and VRH 5, VRL 0. The ADC reading is $24. What is the c) How is the HCS12 ADC powered up? How long must the program delay before using the 10 mV. How many bits are required? analog input voltage for a 10-bit conversion? ADC after powering it up? Q3. Write a section of assembly code to set the ADC registers. The ADC is set up to measure 0 5Volts, the ADC data registers are to be left justified, signed, and 8-bit conversion

Answer 1

(a) Given that, v_min = -5v, v_max = 5v resolution = 10 m we know that resolution = v_max - v_min/2^n-1 so 10 times 10^-3 = 5-(-5)/2^n-1 = 10/2^n - 1 so 2^n - 1 = 1000 2^n = 1001 so n log^2_2 = log_2 1001 = 9,967 so n = 10 bits (b) Given analog voltage range is 0v - 5v \r\n ADC reaching is 24 v. n = 10 v so digital equivalent = 24 resolution = v_max - v_min/2^n - 1 = 5 - 0/ ^10-1 resolution = 5/1023 = 4.887 times 10^-3 v so digital eq = Resolution times Analog input 24 = 4.887 times 10^-3 times Analog input so analog input = 4910.4 v