Analog to Digital Converts
By Ibrahim Kamal
By Ibrahim Kamal
The Electronic circuit
Any Experienced reader may have noticed that the hardware for such a device is very simple (with disregard to the microcontroller). Indeed, you only need to slightly change the design of the DAC explained in this early tutorial. The components on the left part of the schematic are standard in most of the projects, which are the capacitors (C1 and C2), the crystal oscillator (X1), the reset switch (SW1) with the debouncing capacitor (C3) and resistor (R12), and the connector (J1) for ISP programming. The resistor R13 to R32 and LM358 comparator are responsible of converting Digital signals to Analog signals with 10 bits resolution, and adding to that a micro-controller, we get an ADC.
As mentioned before, the purpose of a micro-controller in this application is to generate the analog signals to be compared with the measured input voltage (Vin). The LM358 comparator will give a change of logic level (from 0 to 1) indicating that the simulated analog voltage reached the measured voltage, thus indicating the end of conversion.
References:
- Counting Type ADC, Analog to Digital Converter, http://www.ikalogic.com/
- http://en.wikipedia.org
