Chapter 1 MC9S12C and MC9S12GC Device Overview (MC9S12C128)
56
MC9S12C-Family / MC9S12GC-Family
Freescale Semiconductor
Rev 01.24
1.3.5.4
V
DDA
, V
SSA
— Power Supply Pins for ATD and VREG
V
DDA
, V
SSA
are the power supply and ground input pins for the voltage regulator reference and the analog
to digital converter.
1.3.5.5
V
RH
, V
RL
— ATD Reference Voltage Input Pins
V
RH
and V
RL
are the reference voltage input pins for the analog to digital converter.
1.3.5.6
V
DDPLL
, V
SSPLL
— Power Supply Pins for PLL
Provides operating voltage and ground for the oscillator and the phased-locked loop. This allows the
supply voltage to the oscillator and PLL to be bypassed independently. This 2.5V voltage is generated by
the internal voltage regulator.
NOTE
All V
SS
pins must be connected together in the application. 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
MCU pin load.
Table 1-6. Power and Ground Connection Summary
Mnemonic
Nominal
Voltage (V)
Description
V
DD1, VDD2
2.5
Internal power and ground generated by internal regulator. These also allow an external source
to supply the core V
DD
/V
SS
voltages and bypass the internal voltage regulator.
In the 48 and 52 LQFP packages V
DD2
and V
SS2
are not available.
V
SS1, VSS2
0
V
DDR
5.0
External power and ground, supply to internal voltage regulator.
V
SSR
0
V
DDX
5.0
External power and ground, supply to pin drivers.
V
SSX
0
V
DDA
5.0
Operating voltage and ground for the analog-to-digital converters and the reference for the
internal voltage regulator, allows the supply voltage to the A/D to be bypassed independently.
V
SSA
0
V
RH
5.0
Reference voltage low for the ATD converter.
In the 48 and 52 LQFP packages V
RL
is bonded to V
SSA
.
V
RL
0
V
DDPLL
2.5
Provides operating voltage and ground for the phased-locked loop. This allows the supply voltage
to the PLL to be bypassed independently. Internal power and ground generated by internal
regulator.
V
SSPLL
0
Summary of Contents for MC9S12C Family
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