X4043/45
Figure 5. V
TRIP
Programming Sequence
V
TRIP
Programming
Let:
MDE = Maximum Desired Error
No
Desired
V
TRIP
<
Present Value ?
YES
Execute
V
TRIP
Reset Sequence
MDE
+
Acceptable
Desired Value
Error Range
MDE
–
Error = Actual – Desired
Set V
CC
= desired V
TRIP
New V
CC
applied =
Old V
CC
applied + | Error |
Execute
Set Higher V
TRIP
Sequence
New V
CC
applied =
Old V
CC
applied – | Error |
Power Down
the Device
Execute Reset V
TRIP
Sequence
Ramp V
CC
NO
Output Switches?
(RESET)
YES
Error < MDE
–
Actual V
TRIP
–
Desired V
TRIP
= Error
| Error | < | MDE |
DONE
Error > MDE
+
Control Register
The control register provides the user a mechanism for
changing the block lock and watchdog timer settings.
The block lock and watchdog timer bits are nonvolatile
and do not change when power is removed.
The control register is accessed with a special pream-
ble in the slave byte (1011) and is located at address
1FFh. It can only be modified by performing a byte
write operation directly to the address of the register
and only one data byte is allowed for each register
write operation. Prior to writing to the control register,
the WEL and RWEL bits must be set using a two step
process, with the whole sequence requiring 3 steps.
See "Writing to the Control Register".
The user must issue a stop after sending this byte to
the register to initiate the nonvolatile cycle that stores
WD1, WD0, BP2, BP1, and BP0. The X4043/45 will not
acknowledge any data bytes written after the first byte
is entered.
REV 1.1.17 9/14/01
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Characteristics subject to change without notice.
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XICOR [ XICOR INC. ]
