Datasheet

Section 17 A/D Converter
R01UH0310EJ0500 Rev. 5.00 Page 1025 of 1384
Sep 25, 2012
H8S/2426, H8S/2426R, H8S/2424 Group
17.7.9 Concurrent Operation of Two A/D Converters
When operating two A/D converters concurrently, if conversion by the two converters starts at
different times, the accuracy of conversion may be affected by crosstalk between the two
converters.
When converter Y starts A/D conversion during the period indicated by T
X-Y
in figure 17.13 below
after the start of A/D conversion by converter X, and conversion by converter X is completed
while conversion by converter Y is still in progress, the accuracy of A/D conversion may not be
guaranteed.
When operating two A/D converters concurrently, be sure to conduct adequate evaluation in
advance.
Note: X and Y in "converter X" and "converter Y" indicate either pair of 0 and 1.
Converter X
ADST
Converter Y
ADST
T
X-Y
ANn
in operation
A/D conversion
t
SPL
Wait for conversion Wait for conversion
[Legend]
ANn: Operating channel of converter Y
T
X-Y
: Difference in time when A/D conversion starts
t
SPL
: Input sampling time
Figure 17.13 An Example of Timing Where Accuracy of A/D Conversion is not Guaranteed
Table 17.10 Difference in Time When A/D Conversion Starts (T
X-Y
) in Figure 17.13
T
X-Y
Unit
0 to 10 ADCLK cycles