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MC9S12XD256CAL Datasheet, PDF (558/1348 Pages) Freescale Semiconductor, Inc – This specification describes the function of the clocks and reset generator (CRG). | |||
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Chapter 14 Voltage Regulator (S12VREG3V3V5)
14.2.4 VDDPLL, VSSPLL â Regulator Output2 (PLL) Pins
Signals VDDPLL/VSSPLL are the secondary outputs of VREG_3V3 that provide the power supply for the
PLL and oscillator. These signals are connected to device pins to allow external decoupling capacitors
(220 nF, X7R ceramic).
In Shutdown Mode, an external supply driving VDDPLL/VSSPLL can replace the voltage regulator.
14.2.5 VREGEN â Optional Regulator Enable Pin
This optional signal is used to shutdown VREG_3V3. In that case, VDD/VSS and VDDPLL/VSSPLL must be
provided externally. Shutdown mode is entered with VREGEN being low. If VREGEN is high, the
VREG_3V3 is either in Full Performance Mode or in Reduced Power Mode.
For the connectivity of VREGEN, see device speciï¬cation.
NOTE
Switching from FPM or RPM to shutdown of VREG_3V3 and vice versa
is not supported while MCU is powered.
14.3 Memory Map and Register Deï¬nition
This section provides a detailed description of all registers accessible in VREG_3V3.
If enabled in the system, the VREG_3V3 will abort all read and write accesses to reserved registers within
itâs memory slice.
14.3.1 Module Memory Map
Table 14-2 provides an overview of all used registers.
Table 14-2. Memory Map
Address
Offset
0x0000
0x0001
0x0002
0x0003
0x0004
0x0005
0x0006
0x0007
Use
HT Control Register (VREGHTCL)
Control Register (VREGCTRL)
Autonomous Periodical Interrupt Control Register (VREGAPICL)
Autonomous Periodical Interrupt Trimming Register (VREGAPITR)
Autonomous Periodical Interrupt Period High (VREGAPIRH)
Autonomous Periodical Interrupt Period Low (VREGAPIRL)
Reserved 06
Reserved 07
Access
â
R/W
R/W
R/W
R/W
R/W
â
â
MC9S12XDP512 Data Sheet, Rev. 2.21
558
Freescale Semiconductor
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