Datasheet

Section 17 A/D Converter
Page 1022 of 1384 R01UH0310EJ0500 Rev. 5.00
Sep 25, 2012
H8S/2426, H8S/2426R, H8S/2424 Group
17.7.5 Influences on Absolute Accuracy
Adding capacitance results in coupling with GND, and therefore noise in GND may adversely
affect absolute accuracy. Be sure to make the connection to an electrically stable GND such as
AVss.
Care is also required to insure that filter circuits do not communicate with digital signals on the
mounting board, acting as antennas.
17.7.6 Setting Range of Analog Power Supply and Other Pins
If the conditions shown below are not met, the reliability of the LSI may be adversely affected.
• Analog input voltage range
The voltage applied to analog input pin ANn during A/D conversion should be in the range
AVss ≤ V
AN ≤ Vref.
• Relation between AVss and Vss, and AVcc and Vcc
As the relationship between AVss and Vss, set AVss = Vss. If the A/D converter is not used,
set AVcc = Vcc and AVss = Vss.
• Vref setting range
The reference voltage at the Vref pin should be set in the range Vref ≤ AVcc.