Two Marks Questions with Answers

Two Marks Questions with Answers

 

Q.1 Name any two type of ADCs.

Ans. : Dual slope ADC and successive approximation ADC.

 

Q.2 Calculate the values of  LSB, MSB and full scale output for 8-bit DAC for 0 to 10 V range.

Ans. : Given : n = 8, V_oFS = 10 V

ஃ LSB = 39.21 mV

MSB (128) = 128 × 39.21 = 5 V

 

Q.3 Draw the basic block diagram of ADC interfacing with 8085.

(Refer section 13.6)

 

Q.4 What are the signals handled in ADC interfacing ?

Ans. : The signals handled in ADC interfacing are :

SOC : Start of conversion - Send to start conversion process.

EOC : End of conversion - Indicate the end of conversion.

ALE : In case of multi-channel ADC if is used to latch the address of channel to be selected.

Address : In case of multi-channel ADC address signals are sent to select the desired channel.

 

Q.5 What is the significance of end of conversion signal while interfacing A/D converter to a microprocessor ?

Ans. : End of conversion signal from ADC indicates that the conversion is completed. So that microprocessors can read converted digital word through data bus by enabling the output enable signal after EOC is activated.

 

Q.6 Why ADC and DAC is used in the microprocessor bused system ?

Ans. : Most of the information carrying signals such as voltage, current, charge, temperature, pressure and time are available in the analog form. However, for processing, transmission and storage purposes, it is often more convenient to express such signals in the digital form. When expressed in the digital form, they provide better accuracy and reduce noise.

Moreover, the development in the microprocessor technology has made it compulsory to process data in the digital form and hence ADC is used in the microprocessor based systems.

On the other hand, a digital to analog (D/A) converter is used when a binary output from a digital system must be converted to some equivalent analog voltage or current. For example, if in a particular system a computer is used as a controller, the controlling signal produced by the computer is always digital. The system to be controlled requires the analog signal. Hence in between the computer and the system to be controlled the digital to analog converter is must.

 

Q.7 What are the commonly used ADC's and DAC's ?

Ans. : i) Commonly used ADC's are : ADC 0808/0809, ADC 0804, ADC 7109.

ii) Commonly used DAC's are : DAC 0808, DAC 0830.

 

Q.8 Draw the basic block diagram of ADC interfacing with 8085.

(Refer sections 13.7 and 13.10)

 

Q.9 Draw the 3-bit digital to analog converter block and plot its analog output.

(Refer section 13.1)

 

Q.10 What are the applications of D/A converter interfacing with 8255 ?

(Refer section 13.4)

 

 

University Questions with Answers (Long Answered Questions)

(Regulation 2008)

Dec.-10

Q.1 With neat diagram explain the ADC interface to microprocessor.

(Refer section 13.6) [16]

May-11

Q.2 With neat sketches, Explain the interfacing of D/A converter with 8085 Microprocessor.

(Refer section 13.3) [8]

Q.3 With neat diagram explain the ADC interface to microprocessor.

(Refer section 13.6)       [16]

Q.4 Show and explain the ADC interfacing with 8085 microprocessor.

(Refer section 13.6)       [8]

Dec.-ll

Q.5 With neat sketches, Explain the interfacing of D/A converter with 8085 Microprocessor.

(Refer section 13.3)       [8]

Q.6 With neat diagram explain the ADC interface to microprocessor.

(Refer section 13.6)       [16]

Q.7 Why do we need A/D converter and D/A converter? Draw the block diagram to interface 8085 microprocessor with A/D convertor and D/A convertor.

(Refer section 13.6)       [8]

May-12

Q.8 Draw and describe the interfacing of A/D and D/A converter interfacing to 8085 microprocessor.

(Refer section 13.6) [8]