X40030S14IZ-A Intersil, X40030S14IZ-A Datasheet - Page 8

• Manufacturer Part Number: X40030S14IZ-A
• Description: IC VOLTAGE MONITOR TRPL 14-SOIC
• Manufacturer: Intersil
• Type: Multi-Voltage Supervisorr

Specifications of X40030S14IZ-A

• Number Of Voltages Monitored: 3
• Output: Push-Pull, Totem Pole
• Reset: Active High
• Reset Timeout: Adjustable/Selectable
• Voltage - Threshold: 1.8V, 2.9V, 4.6V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 14-SOIC (3.9mm Width), 14-SOL
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Watchdog Timer
The Watchdog Timer circuit monitors the microprocessor
activity by monitoring the SDA and SCL pins. A standard
read or write sequence to any slave address byte restarts
the watchdog timer and prevents the WDO signal from going
active. A minimum sequence to reset the watchdog timer
requires four microprocessor instructions namely, a Start,
Clock Low, Clock High and Stop. The state of two nonvolatile
control bits in the Status Register determine the watchdog
timer period. The microprocessor can change these
watchdog bits by writing to the X40030, X40031, X40034,
X40035 control register (also refer to page 21).
V1, V2 and V3 Threshold Program
Procedure (Optional)
The X40030 is shipped with standard V1, V2 and V3
threshold (V
will not change over normal operating and storage
conditions. However, in applications where the standard
thresholds are not exactly right, or if higher precision is
needed in the threshold value, the X40030, X40031, X40034,
X40035 trip points may be adjusted. The procedure is
described in the following and uses the application of a high
voltage control signal.
SCL
SDA
SCL
SDA
WDO
TRIP1,
START
FIGURE 4. WATCHDOG RESTART
0.6µs
V
TRIP2,
0
A0h
V
TRIPX
V
TRIP3
1.3µs
8
) voltages. These values
WDT RESET
(X = 1, 2, 3)
7
X40030, X40031, X40034, X40035
FIGURE 3. V
0
STOP
V
TRIPX
CC
/V2MON/V3MON
SET/RESET CONDITIONS
7
Setting a V
There are two procedures used to set the threshold voltages
(V
is higher or lower than the present value. For example, if the
present V
voltage can be stored directly into the V
the new setting is to be lower than the present setting, then it
is necessary to “reset” the V
new value.
Setting a Higher V
To set a V
than the present threshold, the user must apply the desired
V
(Vcc(V1MON), V2MON or V3MON). Then, a programming
voltage (Vp) must be applied to the WDO pin before a START
condition is set up on SDA. Next, issue on the SDA pin the
Slave Address A0h, followed by the Byte Address 01h for
V
Byte in order to program V
valid write operation initiates the programming sequence. Pin
WDO must then be brought LOW to complete the operation.
To check if the V
slightly greater than V
ramp down VXMON and observe when the corresponding
outputs (LOWLINE, V2FAIL and V3FAIL) switch. The voltage
at which this occurs is the V
CASE A
If the desired V
add the difference between V
(actual) to the original V
V
sequence should be repeated again (see Figure 5).
CASE B
If the V
perform the reset sequence as described in the next section.
V
TRIPx
TRIP1
TRIPX
P
0
TRIPx
, 09h for V
00h
threshold voltage to the corresponding input pin
), depending upon if the threshold voltage to be stored
TRIPX
that should be applied to VXMON and the whole
TRIPx
TRIPx
TRIPx
(actual), is higher than the V
is 2.9V and the new V
TRIPX
threshold to a new voltage which is higher
TRIPX
TRIP2
Voltage (x = 1, 2, 3)
is greater than the V
TRIPX
7
TRIPx
, and 0Dh for V
has been set, set VXMON to a value
TRIPX
TRIPx
(that was previously set). Slowly
TRIPX
TRIPx
Voltage (x = 1, 2, 3)
TRIPX
desired. This is your new
. The STOP bit following a
t
voltage before setting the
(actual).
WC
(desired) – V
TRIPx
TRIP3
TRIPx
TRIPX
TRIPX
, and a 00h Data
is 3.2V, the new
cell. If however,
(actual), then
(desired),
TRIPX
August 25, 2008
FN8114.2