5.3 - Data Conversion

Question 1

What signals can be bipolar?

Answer 1

AC analogue signals

Question 2

What signals can be unipolar

Answer 2

DC signals. They fluctuate between 0V and either a positive or negative value but Bebe alternate between both

Question 3

How do digital data signals differ from analogue signals?

Answer 3

They only have two (binary) levels for voltage. High for on, Low for off

Question 4

What is this?

Answer 4

Analogue to Digital Converter (ADC)

Question 5

What is this?

Answer 5

Digital to Analogue Converter (DAC)

Question 6

What does an ADC do?

Answer 6

It converts a continuous input voltage into a digital data stream

Question 7

What are the types of of Analogue to Digital Converter (ADC)?

Answer 7

1. Direct Comparison Converter
2. Ramp Generation A/D Converter
3. Successive Approximation Converter

Question 8

What is the fastest type of Analogue to Digital Converter (ADC)?

Answer 8

The Direct Comparison Converter

Question 9

How many known reference values does a DCC with 8 bit resolution have?

Answer 9

256 Known Values

Question 10

How does a Ramp Analogue to Digital Converter (ADC) work?

Answer 10

It uses a binary counter to feed to a Digital to Analogue Converter (DAC).

Question 11

What is the best application for a ramp generation Analogue to Digital Converter?

Answer 11

Works best in applications where the analogue signal level varies at a slow rate, such as a temperature sensor

Question 12

What is the normal counter replaced with in a Successive Approximation Analogue to Digital Converter (ADC)?

Answer 12

A Successive Approximation Register (SAR)

Question 13

How does a Successive Approximation Register (SAR) count?

Answer 13

The SAR counts by changing the bits from MSB to LSB according to input

Question 14

What is a Digital to Analogue Converter?

Answer 14

A device that takes binary numbers, or combinations of numbers, and changes them into the corresponding voltages

Question 15

How does a Digital to Analogue Converter operate?

Answer 15

A typical DAC converts a sequence of binary digits (Bits) into impulses, which are then processed by a reconstruction filter to smooth out the step response into continuous curves

Question 16

What is one of the simplest Digital to Analogue Converter

Answer 16

The Binary Weighted Ladder network

Question 17

How does a Digital to Analogue Converter operate?

Answer 17

Each bit of a binary input controls a solid state switch. The solid state switch connects either a reference voltage or grounds to a corresponding binary weighted resistor

Question 18

What are the four main types of Digital to Analogue Converter circuits

Answer 18

1. Binary weighted resistor
2. Binary ladder or R-R2 ladder
3. Segmented DAC
4. Delta-sigma DAC

Question 19

How does the ladder R-2R network DAC operate?

Answer 19

Each bit of the binary input controls a solid-state switch, connecting either a reference voltage or a ground to the resistors.

Question 20

In an R-2R ladder network, different resistor values are used?

Answer 20

Only two different values

Question 21

Are the resistor values in an R-2R Ladder network more or less critical than a Binary weighted ladder

Answer 21

In an R-2R ladder network the resistor values are not as critical as in the binary weighted ladder