Datasheet

Pinout and Signal Description
MC9S12DP256 — Revision 1.1
Pinout and Signal Description
Power Supply Pins
MC9S12DP256 power and ground pins are described below and
summarized in Table 6.
External Power
(V
DDX
) and
Ground (V
SSX
)
External power and ground for I/O drivers. Because fast signal
transitions place high, short-duration current demands on the power
supply, use bypass capacitors with high-frequency characteristics and
place them as close to the MCU as possible. Bypass requirements
depend on how heavily the MCU pins are loaded.
External Power
(V
DDR
) and
Ground (V
SSR
)
External power and ground for I/O drivers and input to the internal
voltage regulator. Because fast signal transitions place high,
short-duration current demands on the power supply, use bypass
capacitors with high-frequency characteristics and place them as close
to the MCU as possible. Bypass requirements depend on how heavily
the MCU pins are loaded.
Internal Power
(V
DD1,2
) and
Ground (V
SS1,2
)
Power is supplied to the MCU through V
DD
and V
SS
. Because fast signal
transitions place high, short-duration current demands on the power
supply, use bypass capacitors with high-frequency characteristics and
place them as close to the MCU as possible. This 2.5V supply is derived
from the internal voltage regulator. There is no static load on those pins
allowed. The internal voltage regulator is turned off, if VREGEN is tied to
ground.
V
DDA
, V
SSA
Provides operating voltage and ground for the analog-to-digital
converters. It provides also the reference for the internal voltage
regulator.This allows the supply voltage to the A/D and the reference
voltage to be bypassed independently.
Analog to Digital
Reference
Voltages (V
RH
, V
RL
)
Provides reference voltage and ground for the analog-to-digital
converters.
Freescale Semiconductor, I
Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
nc...