Method Of A/D Conversion (8-Bit Mode) - Renesas M16C Series User Manual

M30245 Group

2.9.10 Method of A/D Conversion (8-bit mode)

Table 2.9.10. The comparison voltage in 8-bit mode compared to 8-bit A/D converter
www.DataSheet4U.com
Comparison
voltage
Vref
Optimal conversion characteristics of 8-bit A/D converter (V
(Result of A/D conversion)
Optimal conversion characteristics in 8-bit mode (V
Figure 2.9.19. The level conversion characteristics of 8-bit mode and 8-bit A/D converter
Rev.2.00 Oct 16, 2006
REJ09B0340-0200
(1) In 8-bit mode, 8 higher-order bits of the 10-bit successive comparison register becomes A/D
conversion result. Hence, if compared to a result obtained by using an 8-bit A/D converter,
the voltage compared is different by 3 V
2.9.10), and differences in stepping points of output codes occur as shown in Figure 2.9.19.
n = 0
V
REF
n = 1 to 255
2
Output code
02
01
00
Output code
(Result of A/D conversion)
8-bit 10-bit
mode mode
09
02
08
07
06
05
01
04
03
02
01
00
00
Note: Differences in stepping points of output code for analog input voltage.
page 233 of 354
/2048 (see what are underscored in Table
REF
8-bit mode
0
V
REF
n
–
x x 0.5
8 10
2
10 30
(Note)
17.5 37.5
8-bit A/D converter
0
V
REF
n
–
x
8
2
= 5.12 V)
REF
Analog input voltage (mV)
= 5.12 V)
REF
10bit-mode
8bit-mode
Analog input voltage (mV)
2. A/D Converter
V
REF
x 0.5
8
2