
88-6 Signal Processing
88.4.3 Linear Errors
Linear errors are the largest and most common errors in an ADC and are easily corrected by sim-
ple calibrations or by additions with and multiplications by correction constants. Linear errors do
no
t
di
stort
th
e
tr
ansfer
fu
nction;
th
ey
on
ly
ch
ange
so
mewhat
th
e
in
put
ra
nge
ov
er
wh
ich
th
e
AD
C
operates.
Figure 88.3 shows the transfer function of an ideal 3 bit ADC with some oset error. e straight
line joining the centers of the code transitions is raised, or oset, by 0.6 LSB, and the bottom graph
sh
ows
th
e
re
sulting
er
ror
. Fi
gure
88.4 sh
ows
an id
eal
3 bi
t
AD
C
wi
th
a +2
5%
ga
in error
. e sl
ope
of the