Chapter 1 MC9S12XHZ Family Device Overview
MC9S12XHZ512 Data Sheet, Rev. 1.06
46
Freescale Semiconductor
1.2.4.3
VDD1, VSS1, VSS2 — Internal Logic 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.
VSS1 and VSS2 are internally connected.
1.2.4.4
VDDA, VSSA — Power Supply Pins for ATD and VREG
VDDA, VSSA are the power supply and ground pins for the voltage regulator and the analog-to-digital
converter.
1.2.4.5
VRH, VRL — ATD Reference Voltage Input Pins
VRH and VRL are the voltage reference 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.
1.2.4.7
VDDM1, VDDM2, VDDM3 — Power Supply Pins for Motor 0 to 3
VDDM1, VDDM2 and VDDM3 are the supply pins for the ports U, V and W. VDDM1, VDDM2 and VDDM3
are internally connected.
1.2.4.8
VSSM1, VSSM2, VSSM3 — Ground Pins for Motor 0 to 3
VSSM1, VSSM2 and VSSM3 are the ground pins for the ports U, V and W. VSSM1, VSSM2 and VSSM3 are
internally connected.
1.2.4.9
VLCD — Power Supply Reference Pin for LCD driver
VLCD is the voltage reference pin for the LCD driver. Adjusting the voltage on this pin will change the
display contrast.