week 9 Flashcards
what is digital to analogue converter (DAC)
a device for converting binary code to an analogue signal.
application examples of DAC
speakers, heating, servo drivers
what is one way of creating a DAC
one benefit and one negative
using an Op-amp configuration
the benefit is that it is the fastest conversion
negative is that is suffering from poor accuracy
what is a resolution?
number of possible output levels the DAC is designed to reproduce
what is the best resolution output for a DAC
greater the number of output levels the better the resolution and performance of the system
what is a maximum sampling frequency
measure of max speed at which a DAC can operate and still generate the correct analogue output voltage
what is an offset voltage and linearity
measurement of output signal to the input binary string
what is a polarity
positive or negative output voltage
some DAC can produce only one of these or both
what is a ADC
analogue to digital converter
what does a sampling rate of 2Hz mean
1 sample is taken every 0.5 second
why is a higher sampling rate better
gives better representation of the analogue signal, but requires more power
advantages using 3-bit flash ADC
fastest type of ADC
disadvantages using 3-bit flash ADC
Using up to 8 bit is cheap enough but anything higher can be expensive
disadvantages of an 8-bit ADC
they are the slowest but the cheapest chips around
