MB91F376G Fujitsu Components, MB91F376G Datasheet - Page 227

• Manufacturer Part Number: MB91F376G
• Manufacturer: Fujitsu Components

Specifications of MB91F376G

• Lead Free Status / Rohs Status: Not Compliant

8. Notes on Using A/D Converter
• About the external impedance of analog input and its sampling time
• About errors
• A/D converter with sample and hold circuit. If the external impedance is too high to keep sufficient sampling
*1 : MB91366GA
*2 : MB91FV360GA/F362GB/F364G/F369GA/F365GB/F366GB/F367GB/F368GB/F376G
Note : The values are reference values.
• To satisfy the A/D conversion precision standard, consider the relationship between the external impedance
• If the sampling time cannot be sufficient, connect a capacitor of about 0.1 µF to the analog input pin.
As |AVRH − AV
• Analog input circuit model
• The relationship between the external impedance and minimum sampling time
time, the analog voltage charged to the internal sample and hold capacitor is insufficient, adversely affecting
A/D conversion precision.
and minimum sampling time and either adjust the resistor value and operating frequency or decrease the
external impedance so that the sampling time is longer than the minimum value.
[External impedance = 0 kΩ to 100 kΩ]
100
90
80
70
60
50
40
30
20
10
0
0
Analog input
Flash products
SS
Minimum sampling time (µs)
| becomes smaller, values of relative errors grow larger.
5
10
15
During sampling : ON
Mask products
20
25
↑
30
35
R
C
18
12
[External impedance = 0 kΩ to 20 kΩ]
20
16
14
10
8
6
2
0
4
0
Flash products*
Mask products*
Flash products
1
Comparator
Minimum sampling time (µs)
2
MB91360G Series
3
1
2
4
Mask products
3.6 kΩ (Max)
3.6 kΩ (Max)
5
R
6
7
30.0 pF (Max)
24.0 pF (Max)
8
C
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