Explaining the principle of the conversion of analog and digital data

DAC is a device that is able to produce an analog voltage equivalent to the digital data provided to him. Simple DAC can be made from the R-2R ladder like the following picture:

DAC is a device That Is Able to Produce an analog voltage equivalent to the digital data provided to uterus. Simple DAC cans be made from the R-2R ladder picture like the Following:
The composition of R-2R ladder 8 bits will divide the voltage value of 0-5 volts in 255 degrees, so that a degree will be worth 5 / 255 Volt (19.5 mV). So if data is 31H (51 decimal) voltage produced is 51 x 19.5 = 994.5 mV = close to 1 volt.The use of IC DAC 0808 will be easier to obtain an analog voltage from the existing digital data. DAC 0808 pin configuration as follows:

An example circuit using the DAC 0808 DAC is shown in the following figure:
In the Figure, R5M  from Vref connected to Vcc, this means the maximum current that flows 5V / 5 M  = 1 mA. Factoring out the output voltage obtained from this current feedback op amp resistance so 1mAx5M  = 5 volts. Therefore, the DAC has a data width of 8 bits, the maximum number 255 (0FFH). Thus if there is data 100 then the result is 100x5/255 = 1.96 VDC can be made from the parallel arrangement of several comparator (depending the desired data width), but processing is not as simple as the DAC. The following are examples of 3 bit DAC.


Facilitate the use of IC ADC 0804 ADC application. Here is a picture ADC0804 pin layout.For more details download it in the format document linked below .....

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