- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄372194 > SP800LEP Low Power Microprocessor Supervisory with Battery Switch-Over PDF資料下載
參數(shù)資料
| 型號： | SP800LEP |
| 英文描述： | Low Power Microprocessor Supervisory with Battery Switch-Over |
| 中文描述： | 低功耗微處理器監(jiān)控與電池開關(guān)過 |
| 文件頁數(shù)： | 19/24頁 |
| 文件大?。?/td> | 196K |
| 代理商： | SP800LEP |
Date: 5/25/04 SP691A/693A/800L/800M Low Power Microprocessor Supervisor with Battery Switch-Over Copyright 2004 Sipex Corporation
19
Figure 30. Watchdog Flow Diagram
START
SET
WDI
LOW
SUBROUTINE
OR PROGRAM LOOP
SET WDI
HIGH
RETURN
END
Watchdog Software Considerations
A way to help the watchdog timer keep a closer
watch on software execution involves setting
and resetting the watchdog input at different
points in the program, rather than "pulsing" the
watchdog input high-low-high or low-high-low.
This technique avoids a "stuck" loop where the
watchdog timer continues to be reset within the
loop, keeping the watchdog from timing out.
Figure 30
shows an example flow diagram
where the I/O driving the watchdog input is set
high at the beginning of the program, set low at
the beginning of every subrouting or loop, then
set high again when the program returns to the
beginning. If the program should "hang" in any
subroutine, the I/O is continually set low and
the watchdog timer is allowed to time out,
causing a reset or interrupt to be issued.
Maximum V
CC
Fall Time
The V
CC
fall time is limited by the propagation
delay of the battery switchover comparator and
should not exceed 0.03V/
μ
s. A standard rule of
thumb for filter capacitance on most regulators
is on the order of 100
μ
F per amp of current.
When the power supply is shut off or the main
battery is disconnected, the associated initial
V
CC
fall rate is just the inverse of 1A/100
μ
F =
0.01V/
μ
s. The V
CC
fall rate decreases with time
as V
CC
falls exponentially, which more than
satisfies the maximum fall-time requirement.
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| SP800LET | Low Power Microprocessor Supervisory with Battery Switch-Over |
| SP800M | Low Power Microprocessor Supervisory with Battery Switch-Over |
| SP800MCN | Low Power Microprocessor Supervisory with Battery Switch-Over |
| SP800MCP | Low Power Microprocessor Supervisory with Battery Switch-Over |
| SP800L | Low Power Microprocessor Supervisory with Battery Switch-Over |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| SP800LET | 制造商:SIPEX 制造商全稱:Sipex Corporation 功能描述:Low Power Microprocessor Supervisory with Battery Switch-Over |
| SP800LET/TR | 制造商:SIPEX 制造商全稱:Sipex Corporation 功能描述:Low Power Microprocessor Supervisory with Battery Switch-Over |
| SP800M | 制造商:SIPEX 制造商全稱:Sipex Corporation 功能描述:Low Power Microprocessor Supervisory with Battery Switch-Over |
| SP800MCN | 制造商:Exar Corporation 功能描述:Power Supply Supervisor Circuit, 16 Pin, Plastic, SOP |
| SP800MCN/TR | 制造商:SIPEX 制造商全稱:Sipex Corporation 功能描述:Low Power Microprocessor Supervisory with Battery Switch-Over |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。