Electronics and Communication Engineering - Digital Electronics - Discussion
Discussion Forum : Digital Electronics - Section 1 (Q.No. 18)
18.
An 8 bit DAC has a full scale output of 2 mA and full scale error of ± 0.5%. If input is 10000000 the range of outputs is
Answer: Option
Explanation:
10000000 = 128, 11111111 = 255
If there is no error, output = 
= 1004μA.
Maximum error = 
Hence range of output 994 to 1014 μA.
Discussion:
10 comments Page 1 of 1.
Akshit Jain said:
5 years ago
@Sujith K.
Here we are considering maximum 8 bit number for the max range.
Here we are considering maximum 8 bit number for the max range.
Sujith k said:
6 years ago
But How this number of steps becomes 255, why not 256?
So, 2^8=256.
So, 2^8=256.
A.R.Poomalai said:
7 years ago
@Priyadarshini.
Convert this binary 10000000 to decimal you will get 128.
Convert this binary 10000000 to decimal you will get 128.
Priyadarshini said:
7 years ago
How 128 as the input range here?
PRAKASH KUMAR SAINI said:
8 years ago
The step size is 2mA/255 = 7.84 μA. Since 10000000 = 12810, the ideal
output should be 128 * 7.84 μA. The error can be as much as
0.5% * 2mA = 10μA.
Thus, the actual output can deviate by this amount from the ideal,
1004μA , so the actual output can be anywhere from 994 to 1014 μA.
output should be 128 * 7.84 μA. The error can be as much as
0.5% * 2mA = 10μA.
Thus, the actual output can deviate by this amount from the ideal,
1004μA , so the actual output can be anywhere from 994 to 1014 μA.
Teju said:
9 years ago
8bit DAC.
Step size= Full scale/number of steps.
Number of steps =255.
=2ma/255=7.84m.
Ideal output to input = step size*input range.
7.84 * 128 = 1004 Ma.
Error = 0.5%*input range.
=0.5%*2ma = 10ma.
Step size= Full scale/number of steps.
Number of steps =255.
=2ma/255=7.84m.
Ideal output to input = step size*input range.
7.84 * 128 = 1004 Ma.
Error = 0.5%*input range.
=0.5%*2ma = 10ma.
(1)
Adi said:
9 years ago
Please give me the formula to be used here.
Sharon said:
1 decade ago
Please give me clear explanation of above expression.
Sudha said:
1 decade ago
2 mA in μA.
Renuka said:
1 decade ago
2000 mentioned above indicates ?
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