|
|
PDF MAX813LCUA Data sheet ( Hoja de datos )
| Número de pieza | MAX813LCUA | |
| Descripción | Low-Cost / uP Supervisory Circuits | |
| Fabricantes | Maxim Integrated | |
| Logotipo |  |
|
Hay una vista previa y un enlace de descarga de MAX813LCUA (archivo pdf) en la parte inferior de esta página. Total 12 Páginas | ||
|
No Preview Available !
19-4334; Rev. 5; 9/95
Low-Cost, µP Supervisory Circuits
_______________General Description
The MAX705-MAX708/MAX813L microprocessor (µP)
supervisory circuits reduce the complexity and number
of components required to monitor power-supply and
battery functions in µP systems. These devices signifi-
cantly improve system reliability and accuracy com-
pared to separate ICs or discrete components.
The MAX705/MAX706/MAX813L provide four functions:
1) A reset output during power-up, power-down, and
brownout conditions.
2) An independent watchdog output that goes low if
the watchdog input has not been toggled within 1.6
seconds.
3) A 1.25V threshold detector for power-fail warning,
low-battery detection, or for monitoring a power sup-
ply other than +5V.
4) An active-low manual-reset input.
The MAX707/MAX708 are the same as the MAX705/
MAX706, except an active-high reset is substituted for
the watchdog timer. The MAX813L is the same as the
MAX705, except RESET is provided instead of RESET.
Two supply-voltage monitor levels are available: The
MAX705/MAX707/MAX813L generate a reset pulse when
the supply voltage drops below 4.65V, while the
MAX706/MAX708 generate a reset pulse below 4.40V.
All four parts are available in 8-pin DIP, SO and µMAX
packages.
_______________________Applications
Computers
Controllers
Intelligent Instruments
Automotive Systems
Critical µP Power Monitoring
__________Typical Operating Circuit
UNREGULATED DC
MAX667
+5V DC LINEAR
REGULATOR
PUSHBUTTON
SWITCH
VCC RESET
PFI PFI
MAX705 WDO
MR
MAX706
MAX813L
PFO
µP
VCC
RESET
I/O LINE
NMI
INTERRUPT
___________________________Features
o µMAX Package: Smallest 8-Pin SO
o Guaranteed RESET Valid at VCC = 1V
o Precision Supply-Voltage Monitor
4.65V in MAX705/MAX707/MAX813L
4.40V in MAX706/MAX708
o 200ms Reset Pulse Width
o Debounced TTL/CMOS-Compatible
Manual-Reset Input
o Independent Watchdog Timer—1.6sec Timeout
(MAX705/MAX706)
o Active-High Reset Output
(MAX707/MAX708/MAX813L)
o Voltage Monitor for Power-Fail or Low-Battery
Warning
______________Ordering Information
PART
MAX705CPA
MAX705CSA
MAX705CUA
MAX705C/D
TEMP. RANGE
0°C to +70°C
0°C to +70°C
0°C to +70°C
0°C to +70°C
PIN-PACKAGE
8 Plastic DIP
8 SO
8 µMAX
Dice*
Ordering Information continued at end of data sheet.
* Dice are specified at TA = +25°C.
**Contact factory for availability and processing to MIL-STD-883.
_________________Pin Configurations
TOP VIEW
MR 1
VCC 2
GND 3
PFI 4
MAX705
MAX706
MAX813L
8 WDO
7 RESET (RESET)
6 WDI
5 PFO
DIP/SO
MR 1
VCC 2
GND 3
PFI 4
MAX707
MAX708
8 RESET
7 RESET
6 N.C.
5 PFO
DIP/SO
( ) ARE FOR MAX813L ONLY.
Pin Configurations continued at end of data sheet.
________________________________________________________________ Maxim Integrated Products 1
Call toll free 1-800-998-8800 for free samples or literature.
1 page  
Low-Cost, µP Supervisory Circuits
______________________________________________________________Pin Description
MAX705/MAX706
DIP/SO µMAX
PIN
MAX707/MAX708
DIP/SO µMAX
MAX813L
DIP/SO µMAX
NAME
FUNCTION
Manual-Reset Input triggers a reset pulse when
pulled below 0.8V. This active-low input has an inter-
1 3 1 3 1 3 MR nal 250µA pull-up current. It can be driven from a TTL
or CMOS logic line as well as shorted to ground with
a switch.
2 4 2 4 2 4 VCC +5V Supply Input
3 5 3 5 3 5 GND 0V Ground Reference for all signals
Power-Fail Voltage Monitor Input. When PFI is less
4 6 4 6 4 6 PFI than 1.25V, PFO goes low. Connect PFI to GND or
VCC when not used.
5
7
5
7
5
7
PFO
Power-Fail Output goes low and sinks current when
PFI is less than 1.25V; otherwise PFO stays high.
Watchdog Input. If WDI remains high or low for
1.6sec, the internal watchdog timer runs out and
WDO goes low (Figure 1). Floating WDI or connect-
6 8 - - 6 8 WDI ing WDI to a high-impedance three-state buffer dis-
ables the watchdog feature. The internal watchdog
timer clears whenever reset is asserted, WDI is three-
stated, or WDI sees a rising or falling edge.
- - 6 - - - N.C. No Connect
Active-Low Reset Output pulses low for 200ms when
triggered, and stays low whenever VCC is below the
reset threshold (4.65V in the MAX705 and 4.40V in the
7 1 7 1 - - RESET MAX706). It remains low for 200ms after VCC rises
above the reset threshold or MR goes from low to high
(Figure 3). A watchdog timeout will not trigger RESET
unless WDO is connected to MR.
Watchdog Output pulls low when the internal watch-
dog timer finishes its 1.6sec count and does not go
high again until the watchdog is cleared. WDO also
82
-
-
8
2
WDO
goes low during low-line conditions. Whenever VCC is
below the reset threshold, WDO stays low; however,
unlike RESET, WDO does not have a minimum pulse
width. As soon as VCC rises above the reset thresh-
old, WDO goes high with no delay.
Active-High Reset Output is the inverse of RESET.
-
-
8
2
7
1
RESET
Whenever RESET is high, RESET is low, and vice
versa (Figure 2). The MAX813L has a RESET output
only.
_______________________________________________________________________________________ 5
5 Page 
Low-Cost, µP Supervisory Circuits
______________________________________________________________________________________ 11
11 Page | ||
| Páginas | Total 12 Páginas | |
| PDF Descargar | [ Datasheet MAX813LCUA.PDF ] | |
Hoja de datos destacado
| Número de pieza | Descripción | Fabricantes |
| MAX813LCUA | Low-Cost / uP Supervisory Circuits | Maxim Integrated |
| Número de pieza | Descripción | Fabricantes |
| SLA6805M | High Voltage 3 phase Motor Driver IC. |
 Sanken |
| SDC1742 | 12- and 14-Bit Hybrid Synchro / Resolver-to-Digital Converters. |
 Analog Devices |
|
DataSheet.es es una pagina web que funciona como un repositorio de manuales o hoja de datos de muchos de los productos más populares, |
| DataSheet.es | 2020 | Privacy Policy | Contacto | Buscar |