MSC711x Application Development System (MSC711xADS) Reference Manual, Rev. 1
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Freescale Semiconductor
Board-Level Functions
Figure 3-4. MSC711xADS Power Up/Power Down Sequence
From a time variant viewpoint, when power is ramped up or down, the 2.5 V supply must at any instant maintain a
voltage that is at least 0.7 V less than that of the 3.3 V supply. Also, at any instant, the 1.2 V supply must maintain
a voltage that is at least 0.7 V less than that of the 2.5 V supply.
Figure 3-5. Power Supply Block Diagram
Time
Voltage
R
a
m
p
-U
p
R
a
m
p
-D
o
w
n
(VIO)t 3.3 V
(VSSTL)t 2.5 V
(VCORE)t 1.2 V
Voltage Difference
Must Be > 0.7V
LDO
12 V to 5 V
DC 2 DC
12 V to 3.3 V
10A Max
LDO 2.5 V
LDO 1.5 V
VTT 1.25 V
LDO 1.2 V
3.3 V
2.5 V
1.5 V
Power
Sequence
1.2 V
1.25 V
5 V
3.3 V 10A
Power Up Reset
