Renesas H8S Series Hardware Manual page 581

Permissible Signal Source Impedance: H8S/2357 Group analog input is designed so that conversion precision is
guaranteed for an input signal for which the signal source impedance is 10 kohm or less. This specification is provided to
enable the A/D converter's sample-and-hold circuit input capacitance to be charged within the sampling time; if the sensor
output impedance exceeds 10 kohm, charging may be insufficient and it may not be possible to guarantee the A/D
conversion precision.
Digital output
Ideal A/D conversion
characteristic
111
110
101
100
011
010
001
000
1 2
1024 1024
Figure 16-8 A/D Conversion Precision Definitions (1)
Digital output
Ideal A/D conversion
characteristic
Actual A/D conversion
characteristic
Offset error
Figure 16-9 A/D Conversion Precision Definitions (2)
Quantization error
1022 1023
FS
1024 1024
Analog
input voltage
Full-scale error
Nonlinearity
error
FS
Analog
input voltage
Rev.6.00 Oct.28.2004 page 553 of 1016
REJ09B0138-0600H