Electrical Characteristics
MPC561/MPC563 Reference Manual, Rev. 1.2
Freescale Semiconductor
F-13
F.8
Power-Up/Down Sequencing
The supply symbols used in this section are described in
.
There are two power-up/down options. Choosing which one is required for an application will depend
upon circuitry connected to 2.6-V compliant pins and dual 2.6-V/5-V compliant pins. Power-up/down
option A is required if 2.6-V compliant pins and dual 2.6-V/5-V compliant pins are connected to the 5-V
supply with a pull-up resistor or driven by 5-V logic during power-up/down. In applications for which this
scenario is not true the power-up/down option B may be implemented. Option B is less stringent and easier
to ensure over a variety of applications.
Refer to
for a list of 2.6 V and dual 2.6V/5 V compliant pins.
The power consumption during power-up/down sequencing will stay below the operating power
consumption specifications when following these guidelines.
NOTE:
The V
DDH
ramp voltage should be kept below 50V/ms and the V
DDL
ramp
rate less that 25V/ms.
F.8.1
Power-Up/Down Option A
The Option A power-up sequence (excluding V
DDKA
) is
1. V
DDH
≤
V
DDL
+ 3.1 V (V
DDH
cannot lead V
DDL
by more than 3.1 V)
2. V
DDH
≥
V
DDL
- 0.5 V (V
DDH
cannot lag V
DDL
by more than 0.5 V)
The first step in the sequence is required is due to gate-to-drain stress limits for transistors in the pads of
2.6-V compliant pins and dual 2.6-V/5-V compliant pins. Damage can occur if gate-to-drain voltage
potential is greater than 3.1 V. This is only a concern at power-up/down. The second step in the sequence
Table F-9. Power Supply Pin Groups
Symbol
Types of Power Pins
V
DDH
(High Voltage Supply Group)
Supply to the 5-V pads for output driver (V
DDH
)
Supply to the analog (QADC64E) circuitry (V
DDA
)
High voltage supply to the flash module (V
FLASH
)
1
1
These power supplies are only available on the MPC563 and MPC564.
V
DDL
(Low Voltage Supply Pins)
Supply to low voltage pad drivers (QVDDL, NVDDL)
Supply to all low voltage internal logic (V
DD
)
Supply to low voltage flash circuitry (V
DDF
)
1
Supply to system PLL
V
DDKA
(Low Voltage Keep-Alive
Supply Pins
2
2
Any supply in the V
DDKA
group can be powered with the V
DDL
if the function which it supplies is not
required during “Keep-alive.”
Supply to IRAMSTBY
Supply to oscillator and other circuitry for keep-alive functions (KAPWR).
Summary of Contents for MPC561
Page 84: ...MPC561 MPC563 Reference Manual Rev 1 2 lxxxiv Freescale Semiconductor...
Page 144: ...Signal Descriptions MPC561 MPC563 Reference Manual Rev 1 2 2 46 Freescale Semiconductor...
Page 206: ...Central Processing Unit MPC561 MPC563 Reference Manual Rev 1 2 3 62 Freescale Semiconductor...
Page 302: ...Reset MPC561 MPC563 Reference Manual Rev 1 2 7 14 Freescale Semiconductor...
Page 854: ...Time Processor Unit 3 MPC561 MPC563 Reference Manual Rev 1 2 19 24 Freescale Semiconductor...
Page 968: ...Development Support MPC561 MPC563 Reference Manual Rev 1 2 23 54 Freescale Semiconductor...
Page 1144: ...Internal Memory Map MPC561 MPC563 Reference Manual Rev 1 2 B 34 Freescale Semiconductor...
Page 1212: ...TPU3 ROM Functions MPC561 MPC563 Reference Manual Rev 1 2 D 60 Freescale Semiconductor...
Page 1216: ...Memory Access Timing MPC561 MPC563 Reference Manual Rev 1 2 E 4 Freescale Semiconductor...
