HD6433044 Hitachi Semiconductor, HD6433044 Datasheet - Page 550

• Manufacturer Part Number: HD6433044
• Description: (HD64 Series) Hitachi Single-Chip Microcomputer
• Manufacturer: Hitachi Semiconductor

6.
Notes: 1. Numeric values are approximate.
*1
Note on Noise: To prevent damage from surges and other abnormal voltages at the analog
input pins (AN
like the one in figure 15-7 between AV
AV
AV
the analog input pins (AN
also occur if A/D conversion is frequently performed in scan mode so that the current that
charges and discharges the capacitor in the sample-and-hold circuit of the A/D converter
becomes greater than that input to the analog input pins via input impedance Rin. The circuit
constants should therefore be selected carefully.
CC
SS
2. Rin: input impedance
. If filter capacitors like the ones in figure 15-7 are connected, the voltage values input to
*1
and V
10 F
REF
Figure 15-7 Example of Analog Input Protection Circuit
0
to AN
and the filter capacitors connected to AN
Rin
*2
7
) and analog reference voltage pin (V
0.01 F
0
to AN
100
0.1 F
7
) will be smoothed, which may give rise to error. Error can
CC
and AV
540
AV
V
AN
AV
SS
REF
. The bypass capacitors connected to
CC
SS
0
to AN
0
to AN
7
REF
), connect a protection circuit
7
must be connected to