X40430 INTERSIL [Intersil Corporation], X40430 Datasheet - Page 7

• Manufacturer Part Number: X40430
• Description: Triple Voltage Monitor with Integrated CPU Supervisor
• Manufacturer: INTERSIL [Intersil Corporation]

Figure 6. V
WEL: Write Enable Latch (Volatile)
The WEL bit controls the access to the memory and to
the Register during a write operation. This bit is a vola-
tile latch that powers up in the LOW (disabled) state.
While the WEL bit is LOW, writes to any address,
including any control registers will be ignored (no
acknowledge will be issued after the Data Byte). The
WEL bit is set by writing a “1” to the WEL bit and
zeroes to the other bits of the control register.
Once set, WEL remains set until either it is reset to 0
(by writing a “0” to the WEL bit and zeroes to the other
bits of the control register) or until the part powers up
again. Writes to the WEL bit do not cause a high volt-
age write cycle, so the device is ready for the next
operation immediately after the stop condition.
Old V
TRIPX
New V
X
applied + | Error |
Set/Reset Sequence (X = 1, 2, 3)
X
applied =
Error < MDE
7
NO
–
No
X40430, X40431, X40434, X40435
V
Set Higher V
Set V
Apply V
> Desired V
TRIPX
V
TRIPX
Output Switches?
Desired V
Actual V
Present Value
X
Decrease V
Reset Sequence
= desired V
V
Desired
Execute
Execute
CC
DONE
Programming
TRIPX
and Voltage
TRIPX
X
TRIPX -
| Error | < | MDE |
TRIPX
<
Sequence
YES
YES
to V
X
TRIPX
X
BP: Block Protect Bits (Nonvolatile)
The Block Protect Bit BP, determines which blocks of
the array are write protected. A write to a protected
block of memory is ignored. The block protect bit will
prevent write operations to half or none of the array.
BP
0
1
100h – 1FFh (256 bytes)
Protected Addresses
Error > MDE
Old V
Execute Reset V
New V
(Size)
X
None
Sequence
applied - | Error |
+
Let: MDE = Maximum Desired Error
Vx = V
Note: X = 1, 2, 3
X
applied =
Desired Value
CC
TRIPX
, VxMON
MDE
MDE
Error = Actual - Desired
+
–
Memory Array
Memory Array
Upper Half of
Error Range
Acceptable
Lock
None
July 29, 2005
FN8251.0