S912XEG384J3VA Datasheet, PDF (816/1324 Pages) Freescale Semiconductor, Inc – MC9S12XEP100 Reference Manual Covers MC9S12XE Family

Chapter 23 Voltage Regulator (S12VREGL3V3V1)
3. Shutdown mode
Controlled by VREGEN (see device level specification for connectivity of VREGEN).
This mode is characterized by minimum power consumption. The regulator outputs are in a high-
impedance state, only the POR feature is available, LVD, LVR and HTD are disabled. The API
internal RC oscillator clock is not available.
This mode must be used to disable the chip internal regulator VREG_3V3, i.e., to bypass the
VREG_3V3 to use external supplies.
23.1.3 Block Diagram
Figure 23-1 shows the function principle of VREG_3V3 by means of a block diagram. The regulator core
REG consists of three parallel subblocks, REG1, REG2 and REG3, providing three independent output
voltages.
MC9S12XE-Family Reference Manual Rev. 1.25
816
Freescale Semiconductor