Data Acquisition and Process Control

The purpose of most electronic systems is to measure or control some physical quantity. The system will need to acquire data from the environment, process this data and record it. Acting as a control system it will also have to interact with the environment.

The flow of information in a typical data acquisition system (DAQ) can be described as follows.

1. The input transducers measure some property of the environment.
2. The output from the transducers is conditioned (amplified, filtered, etc.).
3. The conditioned analog signal is digitized using an analog-to-digital converter (ADC).
4. The digital information is acquired, processed and recorded by the computer.
5. The computer may then modify the environment by outputting control signals.
6. The digital control signals are converted to analog signals using a digital-to-analog converter (DAC).
7. The analog signals are conditioned (eg. amplified and filtered) appropriately for an output transducer.
8. The output transducer interacts with the environment.

 
• Transducers
• Signal Conditioning Circuits
  • De-bouncing the Mechanical Switch
  • Op Amps for Gain, Offset and Function Modification
  • Sample-and-Hold Amplifiers
  • Gated Charge-to-Voltage Amplifier
  • Comparator
• Oscillators
  • Application to Interval Timers
• Digital-to-Analog Conversion
  • Current Summing and IC Devices
  • DAC Limitations
• Analog-to-Digital Conversion
  • Parallel-Encoding ADC (flash ADC)
  • Successive-Approximation ADC
  • Dual-Slope ADC
• Time-to-Digital Conversion
• Problems