ADC0808/ADC0809
Applications Information
(Continued)
DS005672-26
FIGURE 12. Typical Reference and Supply Circuit
DS005672-27
R
A
= R
B
*
Ratiometric transducers
FIGURE 13. Symmetrically Centered Reference
3.0 CONVERTER EQUATIONS
The transition between adjacent codes N and N+1 is given
by:
The output code N for an arbitrary input are the integers
within the range:
(4)
(2)
The center of an output code N is given by:
Where: V
IN
= Voltage at comparator input
V
REF(+)
= Voltage at Ref(+)
V
REF(−)
= Voltage at Ref(−)
V
TUE
= Total unadjusted error voltage (typically
V
REF(+)
÷512)
(3)
11
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