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Mitsubishi microcomputers
M30240 Group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
Preliminary Specifications REV. E
Specifications in this manual are tentative and subject to change
Low Pass Filter Network
5.3 Low Pass Filter Network
All passive components should be in close proximity to pin 78 (LPF), capacitors should be X7R di-
electric or better. The recommended values are listed in Table 1.52 . See Figure 1.120 for schematic
of the LPF.
Figure 1.120: LPF Filter Schematic
Analog V
ss
and Analog V
cc
, pins 77 and 80 should have isolated connections to the digital V
ss
and V
cc
ground planes. Figure 1.121 illustrates the power supply isolation.
Figure 1.121: Power Supply
Table 1.52:
Recommended Values
R 1000
10%
C2 = 680 pf
10%
C1 = 0.1
μ
f
10%
R
C1
C2
Pin 78
(LPF)
Pin 77
A
vss
Digital
V
cc
(on card)
Digital
V
ss
Analog
V
ss
(Pin 77)
Analog
V
cc
(Pin 80)
C
C
Decoupling
Capacitors
Ferrite Beads