Chapter 16 Dual Output Voltage Regulator (VREG3V3V2) Block Description
Freescale Semiconductor
MC9S12C-Family / MC9S12GC-Family
465
Rev 01.24
16.2
External Signal Description
Due to the nature of VREG3V3V2 being a voltage regulator providing the chip internal power supply
voltages most signals are power supply signals connected to pads.
shows all signals of VREG3V3V2 associated with pins.
NOTE
Check device overview chapter for connectivity of the signals.
16.2.1
V
DDR
— Regulator Power Input
Signal V
DDR
is the power input of VREG3V3V2. All currents sourced into the regulator loads flow
through this pin. A chip external decoupling capacitor (100 nF...220 nF, X7R ceramic) between V
DDR
and
V
SSR
can smoothen ripple on V
DDR
.
For entering Shutdown Mode, pin V
DDR
should also be tied to ground on devices without a V
REGEN
pin.
16.2.2
V
DDA
, V
SSA
— Regulator Reference Supply
Signals V
DDA
/V
SSA
which are supposed to be relatively quiet are used to supply the analog parts of the
regulator. Internal precision reference circuits are supplied from these signals. A chip external decoupling
capacitor (100 nF...220 nF, X7R ceramic) between V
DDA
and V
SSA
can further improve the quality of this
supply.
Table 16-1. VREG3V3V2 — Signal Properties
Name
Port
Function
Reset State
Pull Up
V
DDR
—
VREG3V3V2 power input (positive supply)
—
—
V
DDA
—
VREG3V3V2 quiet input (positive supply)
—
—
V
SSA
—
VREG3V3V2 quiet input (ground)
—
—
V
DD
—
VREG3V3V2 primary output (positive supply)
—
—
V
SS
—
VREG3V3V2 primary output (ground)
—
—
V
DDPLL
—
VREG3V3V2 secondary output (positive supply)
—
—
V
SSPLL
—
VREG3V3V2 secondary output (ground)
—
—
V
REGEN
(optional)
—
VREG3V3V2 (Optional) Regulator Enable
—
—
Summary of Contents for MC9S12C Family
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