Engin112-F07-L02-examples

# Engin112-F07-L02-examples - Engin112 Lecture 2 Digital...

This preview shows pages 1–5. Sign up to view the full content.

1 Maciej Ciesielski Department of Electrical and Computer Engineering 09/07/2007 Engin112 – Lecture 2 Digital Systems - Examples Engin112 – 09/07/2007 2 Digital Systems ± Digital systems operate on discrete elements of information y Numbers (e.g., pocket calculator) -> “digits” -> “digital” y Letters (e.g., word processor) y Pictures (e.g., digital cameras) ± Digital systems y Cell phone y Digital camera y MP3 music player y Industrial process controller, etc. ± Some systems use continuous information y Analog clocks y Film cameras y Slide rulers ± For a digital systems to operate on a continuous data, it needs to quantize (digitize) that data first

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
2 Engin112 – 09/07/2007 3 Digital Thermostat ± OK, but how is the conversion done? ± How is digital information stored ± Purpose: control room temperature ± Digital thermostat y Senses temperature and converts it a digital representation y Simple processor compares current and set temperature y If too cold, heater circuit is turned on Engin112 – 09/07/2007 4 Digital Audio processing or storage of digital signal (e.g., MP3)
3 Engin112 – 09/07/2007 5 Analog to Digital Recording Chain Microphone converts acoustic waves to electrical energy. It’s a transducer . Analog signal: continuously varying electrical energy of the sound pressure wave. ADC (Analog to Digital Converter) converts analog to digital electrical signal. Digital signal: digital representation of signal in binary numbers. DAC (Digital to Analog Converter) converts digital signal in computer to analog for your headphones. ADC Engin112 – 09/07/2007 6 Digital Quantization 3-bit quantization: use 3 bits to represent values 0,1,…7 0 1 2 3 4 5 6 7 Amplitude Measure amplitude at each tick of sample clock Time 5 6 7 7 5 4 3 1 2 5 7 5 7 4

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
4 Engin112 – 09/07/2007 7 The Digital Audio Stream ± This is what appears in a sound file, along with a header that indicates the sampling rate, bit depth and other things ± Each number is then converted to binary and stored in a register 5 6
This is the end of the preview. Sign up to access the rest of the document.

### Page1 / 15

Engin112-F07-L02-examples - Engin112 Lecture 2 Digital...

This preview shows document pages 1 - 5. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online