
MC9S12DT128 Device User Guide — V02.09
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Section 21 Port Integration Module (PIM) Block Description
Consult the PIM_9DTB128 Block User Guide for information about the Port Integration Module.
Section 22 Voltage Regulator (VREG) Block Description
Consult the VREG Block User Guide for information about the dual output linear voltage regulator.
Section 23 Printed Circuit Board Layout Proposal
The PCB must be carefully laid out to ensure proper operation of the voltage regulator as well as of the
MCU itself. The following rules must be observed:
Every supply pair must be decoupled by a ceramic capacitor connected as near as possible to the
corresponding pins (C1 –C6).
Central point of the ground star should be the VSSR pin.
Table 23-1 Suggested External Component Values
Component
Purpose
Type
Value
C1
VDD1 filter cap
ceramic X7R
100 … 220nF
C2
VDD2 filter cap
ceramic X7R
100 … 220nF
C3
VDDA filter cap
ceramic X7R
100nF
C4
VDDR filter cap
X7R/tantalum
>= 100nF
C5
VDDPLL filter cap
ceramic X7R
100nF
C6
VDDX filter cap
X7R/tantalum
>= 100nF
C7
OSC load cap
C8
OSC load cap
C9 / C
S
PLL loop filter cap
See PLL specification chapter
C10 / C
P
PLL loop filter cap
C11 / C
DC
DC cutoff cap
Colpitts mode only, if recommended by
quartz manufacturer
R1 / R
PLL loop filter res
See PLL Specification chapter
R2 / R
B
Pierce mode only
R3 / R
S
Q1
Quartz