MC9S12DT128_1002 Datasheet, PDF (74/140 Pages) Freescale Semiconductor, Inc – Device User Guide

Device User Guide — 9S12DT128DGV2/D V02.17
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 converter. It also provides the reference for the internal voltage regulator. This allows the supply
voltage to the ATD and the reference voltage to be bypassed independently.
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.
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 2.5V voltage is generated by
the internal voltage regulator.
NOTE: No load allowed except for bypass capacitors.
2.4.7 VREGEN — On Chip Voltage Regulator Enable
Enables the internal 5V to 2.5V voltage regulator. If this pin is tied low, VDD1,2 and VDDPLL must be
supplied externally.
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