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Section 24 A/D Converter
R01UH0134EJ0400 Rev. 4.00 Page 1285 of 2108
Sep 24, 2014
SH7262 Group, SH7264 Group
Sensor input
This LSI
Sensor output impedance
Low-pass filter
C to 0.1 μF
Up to 5 kΩ
Cin =
15 pF
20 pF
3 kΩ
Note: Values are reference values.
A/D converter
equivalent circuit
Figure 24.10 Example of Analog Input Circuit
24.7.6 Influences on Absolute Precision
Adding capacitance results in coupling with GND, and therefore noise in GND may adversely
affect absolute precision. Be sure to connect AVss, etc. to an electrically stable GND.
Care is also required to insure that filter circuits mounted on the board do not pick up interference
from digital signals (i.e., by acting as antennae).
24.7.7 Note on Usage in Scan Mode and Multi Mode
Starting conversion immediately after having stopped scan mode or multi mode operation may
lead to erroneous results of conversion.
To perform continuous conversion in such cases, set ADST to 0, wait for at least the A/D
conversion time for a single channel to elapse, and then start conversion (ADST = 1). (The A/D
conversion time for a single channel will vary according to the settings of the ADC registers.)