P912XDP512F0MPVR datasheet(66/1348 Pages) FREESCALE

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Chapter 1 Device Overview MC9S12XD-Family

MC9S12XDP512 Data Sheet, Rev. 2.21

Freescale Semiconductor

1.2.4.2

VDDR1, VDDR2, VSSR1, VSSR2 — Power and Ground Pins for I/O Drivers

and for Internal Voltage Regulator

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.

1.2.4.3

VDD1, VDD2, VSS1, VSS2 — Core Power Pins

Power is supplied to the MCU through VDD and VSS. 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 2.5-V 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.

NOTE

No load allowed except for bypass capacitors.

1.2.4.4

VDDA, VSSA — Power Supply Pins for ATD and VREG

VDDA,VSSA are the power supply and ground input pins for the voltage regulator and the analog-to-digital

converters.

1.2.4.5

VRH, VRL — ATD Reference Voltage Input Pins

VRH and VRL are the reference voltage input pins for the analog-to-digital converter.

1.2.4.6

VDDPLL, VSSPLL — 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 2.5-V voltage is generated by

the internal voltage regulator.

NOTE

No load allowed except for bypass capacitors.

P912XDP512F0MPVR 数据表(PDF) 66 Page - Freescale Semiconductor, Inc