**What is resolution of the 4 – bit DAC?**

% Resolution = 1 / ( 2^{N} – 1)

Where N = Number of bit

Therefore, resolution of the 4 – bit DAC is

%
Resolution = 1 / ( 2^{4} – 1)

= 1 / 15

= 6.67%

**A
4 – bit DAC has a step size of 10mV. What is output voltage and percentage
resolution?**

A 4 – bit DAC has 15 ( 2^{4} – 1 )
steps of 10 mV. Therefore the full scale output is equal to 0.15 V ( 15 × 10 mV
). The percentage resolution is ( 10 mV / 0.15 ) × 100 = 6.67%

**A
4 – bit DAC has output voltage of 0.10 V for digital input of 0101. What is
full scale output?**

The full-scale output of the DAC is equal to
product of step size and number of steps.

Full
scale output = 0.10 V ( 2^{4} – 1) = 1.5V

**Explain
the term : Unipolar DAC and Bi – polar DAC**

Unipolar DAC

It is a DAC in which the
binary input is an unsigned number and the output is a positive voltage or
current.

Bi- polar DAC

It is a DAC in which the
binary input is a signed number and the output is a either positive or negative
value.

**What
is reason behind the name ‘R – 2R ladder type DAC’?**

The R – 2R ladder type DAC consists of series
parallel combination of two resistors R and 2R therefore it is known as the R –
2R ladder type DAC.

**Why
high impedance circuit is used at the output of the R – 2R ladder type DAC?**

To prevent loading

**Write
only the name of different types of DAC.**

Different types of DAC

R – 2R Ladder type DAC

Weighted resistor type
DAC

Switched current source
type DAC

Switched capacitor type
DAC

**Which
is the most popular DAC?**

The R – 2R type DAC

**Which
is the simplest type ADC?**

Counter

**Which
is the fastest type ADC?**

Flash or parallel or simultaneous

**Which
is the slowest type ADC?**

Dual slope

**By
which factor the input of the weighted resistor DAC is amplify?**

The input of the Weighted resistor DAC is
amplified by the ratio of the feedback resistor to the input resistor.

**Describe
the disadvantage of the weighted resistor type DAC**

Disadvantage

There must be each bit
position of the digital input for different value of precision resistor.

**What
are the different types of the switched type voltage source DACs? Why it is
called as switched type voltage source DACs?**

The R – 2R type DAC and weighted resistor type
DAC are the examples of the voltage source DACs. When an input position goes
high, the output high voltage switched in the circuit which is summed to other
input voltages, therefore it is called as switched type voltage source DAC.

**What
is advantage of the current source type DACs over the voltage source type DACs?**

The switching in and out of the current type
DACs is faster than the voltage source type DACs.

**Give
reason ‘ The switched current type DAC is sometime called as multiplying DAC’**

When the output of the switched current type DAC is product of digital input and analog reference voltage, it is called as multiplying DAC.

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