microcontroller - ADC & DAC
One of the common and important feature available with microcontrollers is ADC (Analog to Digital Conversion). Where as DAC (Digital to Analog Conversion) is available in selected micro-controllers only.
Most of the data aquisition systems and data displaying sytems use the ADC feature of the micro-controller to convert external data voltage level or signals to digital format. The digital data thus obtained may be displayed suitably or recorded or transmitted to main processing unit.
On the other hand, DAC is used to convert Digital data into a wave form generation or required signal generation etc. The Digital Video or Audio signals will be converted to analog signals in mobiles, televisions etc.
Effectiveness and control of ADC / DAC in micro-controllers:
All the control of ADC/DAC are controlled through the specific registers in mocro-controller, which holds transmission data, control system like, speed, accuracy, channel number etc. The exact register control is dependent on the micro-controller selected for the purpose. So, you should select the micro-controller, which exactly suits your ADC/DAC requirements of the project.
Resolution is the one of the important feature to be noted for a micro-controller. Most of the micro-controllers support 8bit (0-255), 10bit (0-1023) and 12bit(0-4095) resolution. It means the micro-controller can convert ADC / DAC to upto 8 or 10 or 12 bits resolution. So, if you need to convert an anolog signal to 10 bit digital resolution, then 8 bit is not suitable. You have to select atleast 10 bit resolution ADC/DAC supported micro-controller.
Speed is the another important feature to be considered for ADC/DAC. High speed of conversion makes more samples per second and can generate accurate signal input status as well as can convert signals for higher frequencies. So, select the micro-controller which matches your sampling rate and frequency requirements.
Accuracy is of conversion is also one of the feature to be noted for a micro-controller. Most of the micro-controllers lost accuracy at higher speed of conversions. Due to loss of accuracy the exact data input or output analysis may effected and overall performance of the data aquisition or wave form may be effected.
Number of Channels is also to be considered as per the requirement of the project. Some times, more data aquisition channels or more varieties of wave form outputs may be needed. So, you have to select the suitable micro-controller which supports the channels required for the project.
So, for ADC/DAC requirement, select the micro controller which supports all the features as required for the project w.r.t. cost and purpose of the project.
Say, You may require to convert an analog signal from remote area to digital format and transmit to a central processing unit. Then select micro-controller which has required ADC features discussed above and data trasmitting features as well.
ENJOY. GOOD LUCK TO YOU.