mc9s12xs128 Freescale Semiconductor, Inc, mc9s12xs128 Datasheet - Page 493

• Manufacturer Part Number: mc9s12xs128
• Description: Hcs12 Microcontrollers 16-bit Automotive Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

In Shutdown Mode an external supply driving VDD/VSS can replace the voltage regulator.
17.2.4
Signals VDDF/VSS are the secondary outputs of VREG_3V3 that provide the power supply for the NVM
logic. These signals are connected to device pins to allow external decoupling capacitors (220 nF, X7R
ceramic).
In Shutdown Mode an external supply driving VDDF/VSS can replace the voltage regulator.
17.2.5
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
(100 nF...220 nF, X7R ceramic).
In Shutdown Mode, an external supply driving VDDPLL/VSSPLL can replace the voltage regulator.
17.2.6
Signals VDDX/VSS are monitored by VREG_3V3 with the LVR feature.
17.2.7
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 specification.
17.2.8
This pin provides the signal selected via APIEA if system is set accordingly. See
Periodical Interrupt Control Register (VREGAPICL)
for details.
For the connectivity of VREG_API, see device specification.
17.3
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. See device level specification for details.
Freescale Semiconductor
Memory Map and Register Definition
VDDF — Regulator Output2 (NVM Logic) Pins
VDDPLL, VSSPLL — Regulator Output3 (PLL) Pins
VDDX — Power Input Pin
VREGEN — Optional Regulator Enable Pin
VREG_API — Optional Autonomous Periodical Interrupt Output Pin
is not supported while MCU is powered.
Switching from FPM or RPM to shutdown of VREG_3V3 and vice versa
S12XS Family Reference Manual, Rev. 1.10
NOTE
and
17.4.8, “Autonomous Periodical Interrupt (API)
Voltage Regulator (S12VREGL3V3V1)
17.3.2.3, “Autonomous
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