MC9S12Q128_10 Datasheet, PDF (56/644 Pages) Freescale Semiconductor, Inc – HCS12 Microcontrollers

Chapter 1 MC9S12Q Device Overview (MC9S12Q128-Family)
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.
Table 1-6. Power and Ground Connection Summary
Mnemonic
V_{DD1, VDD2}
V_{SS1, VSS2}
V_DDR
V_SSR
V_DDX
V_SSX
V_DDA
V_SSA
V_RH
V_RL
V_DDPLL
V_SSPLL
Nominal
Voltage (V)
Description
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.
0
In the 48 and 52 LQFP packages V_DD2 and V_SS2 are not available.
5.0
External power and ground, supply to internal voltage regulator.
0
5.0
External power and ground, supply to pin drivers.
0
5.0
Operating voltage and ground for the analog-to-digital converters and the reference for the
0
internal voltage regulator, allows the supply voltage to the A/D to be bypassed independently.
5.0
Reference voltage low for the ATD converter.
0
In the 48 and 52 LQFP packages V_RL is bonded to V_SSA.
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
0
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.
56
MC9S12Q128
Freescale Semiconductor
Rev 1.10