MN101C115 Datasheet, PDF (130/170 Pages) Panasonic Semiconductor – Request for your special attention and precautions in using the technical information and semiconductors described in this book

Chapter 6 A/D Conversion Functions
The following items must be implemented to maintain the accuracy of the
A/D converter:
1. Use a maximum input pin impedance, R, of 500kΩ^∗1 with an external
capacitor, C, that is minimum 1,000pF and maximum 1µF^∗1.
2. Take the RC time into consideration when setting the A/D conversion
interval.
3. Changing the output level of the microcomputer or switching peripheral
circuitry on or off when the A/D converter is in use may cause the
analog input pin or current pin to fluctuate resulting in a loss of
precision. During setup and evaluation, verify the waveform of the
analog input pin.
Equivalent circuit of
analog signal output
R
Microcomputer
A/D input pin
C
∗1
1 µF≥C≥1000pF
where R≤500kΩ
Vss
∗1 These values are reference values.
Figure 6-2-2 Recommended Circuit When Using A/D Conversion
116 A/D Converter Control Registers