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Chapter 14 Voltage Regulator (S12VREG3V3V5)
MC9S12XDP512 Data Sheet, Rev. 2.17
558
Freescale Semiconductor
14.2.4
VDDPLL, VSSPLL — Regulator Output2 (PLL) Pins
Signals V
DDPLL
/V
SSPLL
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 V
DDPLL
/V
SSPLL
can replace the voltage regulator.
14.2.5
V
REGEN —
Optional Regulator Enable Pin
This optionalsignal isused to shutdown VREG_3V3.In thatcase, V
DD
/V
SS
and V
DDPLL
/V
SSPLL
must be
provided externally. Shutdown mode is entered with VREGEN being low. If VREGEN is high, the
VREG_3V3 is either in full peformance mode or in reduced power mode.
For the connectivity of VREGEN, see device specification.
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 Definition
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
it’s 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
Use
Access
0x0000
HT Control Register (VREGHTCL)
—
0x0001
Control Register (VREGCTRL)
R/W
0x0002
Autonomous Periodical Interrupt Control Register (VREGAPICL)
R/W
0x0003
Autonomous Periodical Interrupt Trimming Register (VREGAPITR)
R/W
0x0004
Autonomous Periodical Interrupt Period High (VREGAPIRH)
R/W
0x0005
Autonomous Periodical Interrupt Period Low (VREGAPIRL)
R/W
0x0006
Reserved 06
—
0x0007
Reserved 07
—