NEC 78014Y Series User Manual page 261

(6) Interrupt request flag (ADIF)
The interrupt request flag (ADIF) is not cleared even if the A/D converter mode register (ADM) is changed.
Caution is therefore required since, if a change of analog input pin is performed during A/D conversion, the A/
D conversion result and ADIF for the pre-change analog input may be set just before the ADM rewrite, and when
ADIF is read immediately after the ADM rewrite, ADIF may be set despite the fact that the A/D conversion for
the post-change analog input has not ended. (Refer to Figure 14-10.)
When the A/D conversion is stopped, the ADIF must be cleared before restarting.
A/D conversion
(7) AV
DD
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The AV
to ANI7/P17.
Therefore, be sure to apply the voltage at the same level as V
where the power supply is switched to the back-up power supply.
Figure 14-10. A/D Conversion End Interrupt Request Generation Timing
Rewriting ADM
(ANln conversion starts)
ANIn
ADCR
INTAD
pin
pin is the analog circuit power supply pin, and supplies power to the input circuits of ANI0/P10
DD
Figure 14-11. AV
Main Power Supply
CHAPTER 14 A/D CONVERTER
Rewriting ADM
(ANlm conversion starts)
ANIn
ANIn
as shown in Figure 14-11, even in an application
DD
Pin Connection
DD
Back up
Capacitor
ADIF is set, but conversion
of ANlm is not completed
ANIm ANIm
ANIn ANIm
AV
REF
V
DD
AV
DD
V
SS
AV
SS
ANIm
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