參數(shù)資料
型號(hào)： MAX807
廠商： Maxim Integrated Products, Inc.
英文描述： Full-Featured レP Supervisory Circuit with 【1.5eset Accuracy
中文描述： 功能完備的微處理器監(jiān)控電路，提供±1.5%的復(fù)位門(mén)限精度
文件頁(yè)數(shù)： 11/16頁(yè)
文件大?。?/td> 116K
代理商： MAX807
M
Full-Featured μP S upervisory Circ uit with
±1.5% Reset Ac c urac y
______________________________________________________________________________________
11
(see the Chip-Enable Propagation Delay vs. CE OUT
Load Capacitance graph in the Typical Operating
Characteristics). The CE propagation delay is produc-
tion tested from the 50% point on CE IN to the 50%
point on CE OUT using a 50
driver and 50pF of load
capacitance (Figure 8). For minimum propagation
delay, minimize the capacitive load at CE OUT and use
a low output-impedance driver.
Chip-Enable Output
In the enabled mode, the impedance of CE OUT is equiv-
alent to 75
in series with the source driving CE IN. In the
disabled mode, the 75
transmission gate is off and CE
OUT is actively pulled to the higher of V
CC
or V
BATT
. This
source turns off when the transmission gate is enabled.
Low-Line Comparator
The low-line comparator monitors V
CC
with a threshold
voltage typically 52mV above the reset threshold, with
13mV of hysteresis. Use LOW LINE to provide a non-
maskable interrupt (NMI) to the μP when power begins
to fall, to initiate an orderly software shutdown routine.
In most battery-operated portable systems, reserve
energy in the battery provides ample time to complete
the shutdown routine once the low-line warning is
encountered, and before reset asserts. If the system
must contend with a more rapid V
CC
fall time—such as
when the main battery is disconnected, a DC-DC con-
verter shuts down, or a high-side switch is opened dur-
ing normal operation—use capacitance on the V
CC
line
to provide time to execute the shutdown routine (Figure
9). First calculate the worst-case time required for the
system to perform its shutdown routine. Then, with the
worst-case shutdown time, the worst-case load current,
and the minimum low-line to reset threshold (V
LR(min)
),
calculate the amount of capacitance required to allow the
shutdown routine to complete before reset is asserted:
C
HOLD
= (I
LOAD
x t
SHDN
) / V
LR
(min)
where t
SHDN
is the time required for the system to com-
plete the shutdown routine, and includes the V
CC
to
low-line propagation delay; and where I
LOAD
is the cur-
rent being drained from the capacitor, V
LR
is the low-
line to reset threshold.
V
CE IN
RESET
THRESHOLD
CE OUT
RESET
RESET
26
μ
s
28
μ
s
26
μ
s
MAX807
CE IN
50pF
C
LOAD
CE OUT
GND
V
RST
MAX
50
DRIVER
V
CC
Figure 7. Reset and Chip-Enable Timing
Figure 8. CE Propagation Delay Test Circuit
GND
V
CC
TO
μ
P NMI
C
HOLD
C
HOLD
> I
LOAD
x t
SHDN
V
LR
4.5V to 5.5V
LOW LINE
MAX807
REGULATOR
Figure 9. Using LOW LINE to Provide a Power-Fail Warning to
the μP
相關(guān)PDF資料
PDF描述
MAX807_CPE Full-Featured レP Supervisory Circuit with 【1.5eset Accuracy
MAX807_CWE Full-Featured レP Supervisory Circuit with 【1.5eset Accuracy
MAX807_EPE Full-Featured レP Supervisory Circuit with 【1.5eset Accuracy
MAX807_EWE Full-Featured レP Supervisory Circuit with 【1.5eset Accuracy
MAX807_MJE Full-Featured レP Supervisory Circuit with 【1.5eset Accuracy
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
MAX807_CPE 制造商:MAXIM 制造商全稱:Maxim Integrated Products 功能描述:Full-Featured レP Supervisory Circuit with 【1.5eset Accuracy
MAX807_CWE 制造商:MAXIM 制造商全稱:Maxim Integrated Products 功能描述:Full-Featured レP Supervisory Circuit with 【1.5eset Accuracy
MAX807_EPE 制造商:MAXIM 制造商全稱:Maxim Integrated Products 功能描述:Full-Featured レP Supervisory Circuit with 【1.5eset Accuracy
MAX807_EWE 制造商:MAXIM 制造商全稱:Maxim Integrated Products 功能描述:Full-Featured レP Supervisory Circuit with 【1.5eset Accuracy
MAX807_MJE 制造商:MAXIM 制造商全稱:Maxim Integrated Products 功能描述:Full-Featured レP Supervisory Circuit with 【1.5eset Accuracy
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。

采購(gòu)需求

(若只采購(gòu)一條型號(hào)，填寫(xiě)一行即可)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

*型號(hào) *數(shù)量 廠商 批號(hào) 封裝
添加更多采購(gòu)

我的聯(lián)系方式

*
*
*