MC9S12A128 MOTOROLA [Motorola, Inc], MC9S12A128 Datasheet - Page 54

• Manufacturer Part Number: MC9S12A128
• Description: Microcontroller unit (MCU)
• Manufacturer: MOTOROLA [Motorola, Inc]

MC9S12A128 Device Guide — V01.01
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:
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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 V
Use low ohmic low inductance connections between V
V
Keep traces of V
C11 and Q1 as small as possible.
Do not place other signals or supplies underneath area occupied by C7, C8, C10 and Q1 and the
connection area to the MCU.
Central power input should be fed in at the V
SSPLL
must be directly connected to V
SSPLL
, EXTAL and XTAL as short as possible and occupied board area for C7, C8,
SSR
.
DDA
SSR
/V
pin.
SSA
SS1
pins.
, V
SS2
and V
SSR
.