X4643 XICOR [Xicor Inc.], X4643 Datasheet - Page 4

• Manufacturer Part Number: X4643
• Description: CPU Supervisor with 64K EEPROM
• Manufacturer: XICOR [Xicor Inc.]

X4643/5 – Preliminary Information
Setting the V
This procedure is used to set the V
lower voltage value. It is necessary to reset the trip
point before setting the new value.
To set the new V
bit in the control register, then apply the desired V
threshold voltage to the V
voltage, V
byte of “00” data. The stop bit following a valid write
operation initiates the V
Bring WP LOW to complete the operation.
Figure 2. Reset V
Figure 3. Sample V
REV 1.26 4/30/02
SCL
SDA
WP
V
Adj.
TRIP
P
, to the WP pin and 2 byte address and 1
TRIP
0 1 2 3 4 5 6 7
TRIP
TRIP
Voltage
A0h
TRIP
voltage, start by setting the WEL
Level Sequence (V
RESET
TRIP
Reset Circuit
CC
pin and the programming
programming sequence.
4.7K
0 1 2 3 4 5 6 7
TRIP
to a higher or
V
P
CC
= 12-15V
00h
> 3V. WP = 12-15V, WEL bit set)
1
2
3
4
www.xicor.com
TRIP
X4643
SOIC
0 1 2 3 4 5 6 7
8
7
6
5
Resetting the V
This procedure is used to set the V
voltage level. For example, if the current V
and the new V
be reset. When V
thing less than 1.7V. This procedure must be used to
set the voltage to a lower value.
To reset the new V
WEL bit in the control register, apply V
gramming voltage, V
address and 1 byte of “00” data. The stop bit of a valid
write operation initiates the V
sequence. Bring WP LOW to complete the operation.
03h
Adjust
TRIP
Run
TRIP
TRIP
Characteristics subject to change without notice.
must be 4.0V, then the V
TRIP
0 1 2 3 4 5 6 7
V
Voltage
P
P
is reset, the new V
, to the WP pin and 2 byte
voltage start by setting the
00h
TRIP
SCL
SDA
TRIP
CC
TRIP
programming
µC
to a “native”
and the pro-
TRIP
TRIP
is some-
is 4.4V
4 of 22
must