Hey guys. I am in australia. Below is a question we have been set for a course i am doing. i am not looking for any final answers. Just how o even get started. to put it in perspective, our lecture has said "I can't answer the questions as i don't know, your best referance is wikipedia or google". Now i know every single piece of theory about ADC's and DAC's, but no idea on how its done in multisim. I have theorys but none actually work. Anway here it is.
Assignment question You are required to convert a 0 -12 V analog signal into a 12 bit digital signal (Analog to Digital Conversion, ADC).
- The frequency of the analog signal is 20 KHz.
- The resultant digital signal is to conform to the requirements of the Gray scale in that only one bit is to change for each quantisation level change.
- The digital signal is also to conform to the “A Law” nonlinearity (Communications companding) in that the digital step has a greater sensitivity at the low voltage level than at the higher voltage level.
- The output of the ADC is used to illuminate three lights
Green > 1/2 VmaxAmber > 5/9 V maxRed >2/3 Vmax The Digital signal is converted back to an analog signal but each digital bit step increase has the same analog magnitude change, the digital signal is considered a linear function of voltage. The design is to be simulated using:NI circuit design suite (Student edition) (10.0.01) 2009 National Instruments
Can you e-mail me on:
elmoatplayschool@hotmail.com, as my e-mail linked to this forum is my work one but i am on holidays trying to do this assignemnt.
thanks so much
kieran
