mc33702 Freescale Semiconductor, Inc, mc33702 Datasheet - Page 20

• Manufacturer Part Number: mc33702
• Description: 3.0 A Switch-mode Power Supply With Linear Regulator
• Manufacturer: Freescale Semiconductor, Inc

33702
20
Switcher Output
Notes
Voltage Margining
LDO Output: x=0
13.
Command Byte)
Command Byte)
Programming
Operation
Watchdog
(As a 2nd
(As a 2nd
The Watchdog feature will be turned ON automatically
after receiving any other valid command byte changing
watchdog time.
Table 5. Command Byte Definitions
x
=1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Address
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
0
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
0
0
1
1
1
1
1
1
1
1
Value
0
0
0
0
0
1
1
1
1
0
0
0
1
1
1
1
0
0
0
0
0
0
1
1
1
1
Freescale Semiconductor, Inc.
0
1
1
1
0
0
1
1
0
0
1
1
0
1
1
0
0
1
1
0
0
0
0
1
0
0
For More Information On This Product,
0
0 Output Normal
1
0
1
0
1
0
1
1
0
1
0
1
0
1
0
0
0
1
0
1
0
1
0
1
1st Command
1st Command
WD 1280 ms
WD 1280 ms
WD 320 ms
WD 320 ms
WD 80 ms
WD 20 ms
WD 80 ms
WD 20 ms
(Note 13)
WD OFF
WinOFF
WinOFF
WinOFF
WinOFF
WinON
WinON
WinON
WinON
Action
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Security in Writing Commands
inadvertently latched after a false command. To improve the
security level, a so-called first command is defined to initiate
each write communications.
to the related operation one, followed by a null value field (all
zeros).
master sends the first command before the Command Byte for
the intended operation.
Voltage Margining Operation
sends the first command followed by the specific Command
Byte to set the required voltage margining for either the LDO or
the switcher (see
both LDO and switcher, two specific commands must be issued
in sequence after the first command, one for each supply.
Watchdog Programming Operation
sends a watchdog first command followed by a command byte
selecting, or confirming, the watchdog period according to the
options listed in
watchdog command is written into the device, provided it
arrives during the window open time. The Command 01100000
sent twice will shut the time OFF, and the watchdog function will
be disabled. Any other valid watchdog command turns on the
timer again.
All writing operations are critical and must not be
A first command has the Command Byte address field equal
After starting the communication in Writing mode, the master
Note x bits are defined in
For watchdog operation control, the master periodically
The internal watchdog timer will be cleared each time a
Note x bits are defined in
First Byte for Watchdog Programming
MOTOROLA ANALOG INTEGRATED CIRCUIT DEVICE DATA
First Byte for Voltage Margining
First Command
0 0
0 1
Table 6
Figure 17. Voltage Margining Programming
001 00000
011 00000
Figure 18. Watchdog Timer Programming
Table 6. First Command Definitions
1
1
0 0 0 0 0
0 0 0 0 0
summarizes first command definitions. The
Table
Figure
(One Supply Only)
5. Also see
17). To achieve a simultaneous set for
Ack
Table
Ack
Table
0
0
Watchdog Programming
Figure
5.
5.
0
1
Voltage Margining
Command Byte
Command Byte
1
1
Operation
18.
x
x
x
x
x
x
x
x
x
x