Determine the resolution and the quantization error in volts for a 4-bit A/D converter that has a full scale range of EFSR =5 V . If the desired quantization error should be within 1 mV, how many bits are needed?

Respuesta :

Answer:

minimum of 12 bits is required

Explanation:

Full scale range Ef = 5v = L

Resolution [tex]R_{ADC} = \frac{L}{2^n -1}[/tex]

n = 4 bit

[tex]R_{ADC} = \frac{5}{2^4 -1} = 0.333 V

Quartization error  is

[tex] \epsilon = \frac{1}{2} R_{ADC}[/tex]

               [tex]= \frac{1}{2} 0.333 = 0.166 V[/tex]

we know if error is less than 0.001 V then we have

[tex]1/2 R_{ADC} \leq 0.001[/tex]

[tex]R-{ADC} \leq 0.002[/tex]

[tex]0.002\geq \frac{L}{2^n -1}[/tex]

[tex] \frac{L}{2^n -1} \leq 0.002[/tex]

[tex]\frac{L}{0.002} \leq 2^n -1[/tex]

Solving for n we get

[tex]n\geq 11.288[/tex]

n = 12

Therefore minimum of 12 bits is required