# How many bits should be employed to obtain a resolution

#### killersanta

1. Homework Statement
An A/D converter is to operate with a full-scale voltage of 10V. How many bits should be employed to obtain a resolution of 0.01%?

2. Homework Equations
Resolution = Full Scale voltage / (2N - 1)

3. The Attempt at a Solution

.01% * 10 V = .01/100 * 10 V = .001

.001 = 10 V / (2N - 1)

N = 13.2879 = 14 bits

I am just learning this stuff, but 14 bits seems high to me. I believe the mistake is in the Resolution. I am just assuming they me the resolution is .01% of the full scale voltage, this seems wrong to me.

Thanks for any help!
1. Homework Statement

2. Homework Equations

3. The Attempt at a Solution

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#### SteamKing

Staff Emeritus
Homework Helper
0.01 / 100 = 0.0001 not 0.001

#### killersanta

Wow, thank for the quick reply.

I know that, but don't you times it by 10 V? Isn't the units for resolution volts? I assumed when they said "resolution of 0.01%," I assumed this was .01% of the full scale voltage. Is that wrong to assume?
Should resolution just equal .0001? Then N= 16.6 = 17 bits?

Staff Emeritus