Fujitsu F2MCTM-16LX Hardware Manual page 371

The sampling time must be set according to drive impedance R
following condition is not met, the conversion accuracy will not be guaranteed.
≤ 1.5kΩ :
• R
ext
•- 4.5 V ≤ AV
• 4.0 V ≤ AV
>
• R 1.5kΩ : The sampling time must be set greater than T
ext
• 4.5 V ≤ AV
• 4.0 V ≤ AV
Setting of Comparing Time (CT2 to CT0 bits)
Table 18.3-7 Relation between CT2 to CT0 Bits and Comparing Time
CT2 CT1
0 0
0 0
0 1
0 1
1 0
1 0
1 1
1 1
The comparing time must be set according to the analog power supply voltage AV
condition is not met, the conversion accuracy will not be guaranteed.
• 4.5 V ≤ AV
• 4.0 V ≤ AV
< 5.5 V: The sampling time must be set greater than 0.5 µs.
CC
< 4.5 V: The sampling time must be set greater than 1.2 µs.
CC
< 5.5 V: T = (2.52 kΩ+R
CC samp
< 4.5 V: T = (13.6 kΩ+R
CC samp
CT0 Setting of comparing
time
0 22 machine cycles
1 33 machine cycles
0 44 machine cycles
1 66 machine cycles
0 88 machine cycles
1 132 machine cycles
0 176 machine cycles
1 264 machine cycles
< 5.5 V: The comparing time must be set greater than 1.00 µs.
CC
< 4.5 V: The comparing time must be set greater than 2.00 µs.
CC
CHAPTER 18 8-/10-BIT A/D CONVERTER
connected to analog input. If the
ext
given by the following formula.
samp
) × 10.7 pF × 7
ext
) × 10.7 pF × 7
ext
Setting example (φ: Internal
operating frequency)
φ= 20 MHz: 1.1 µs
φ= 24 MHz: 1.4 µs
φ= 24 MHz: 1.8 µs
φ= 24 MHz: 2.75 µs
φ= 8 MHz: 11.0 µs
φ= 16 MHz: 8.25 µs
φ= 20 MHz: 8.8 µs
φ= 24 MHz: 11.0 µs
. If the following
CC
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