1 Lab

1. If your ADC is 8-bits, how many digital levels do you have? What is the resolution of this ADC if it operates in the range of 0-5V, e.g. looking at Figure 1, what is $\Delta$ in volts?. If the input is 2.5V, what is the output?
2. Build the circuit shown in Figure 2.

   Figure 2: ADC0804 Tester

   

   Make sure to have separate buses for the analog ground and the digital ground (See Figure 3). Then connect them at a single point on your board. Otherwise, there will be noise on the analog signals due to the fast switching of the digital portion of the chip. Datasheet of ADC0804.

   Figure 3: Analog and digital ground symbols

   

3. Use a variable pot to control the input to the ADC. Connect the output to the LEDs on your protoboard. Verify that it works properly.
4. Design a computer program that takes in the value for the ADC and if it is greater than 2.5V then output a 1, otherwise output a 0.
5. Implement your control system and verify its operation in hardware as shown in Figure 4.

   Figure 4: System overview with the variable resistor represents the variable output of a temperature sensor.