Motor de Búsqueda de Datasheet de Componentes Electrónicos
  Spanish  ▼
ALLDATASHEET.ES

X  

FM31T372-G Datasheet(PDF) 5 Page - Ramtron International Corporation

No. de pieza FM31T372-G
Descripción Electrónicos  System Supervisor & Temperature Compensated RTC(TCXO) with Embedded Crystal
Download  26 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
Fabricante Electrónico  RAMTRON [Ramtron International Corporation]
Página de inicio  http://www.ramtron.com
Logo RAMTRON - Ramtron International Corporation

FM31T372-G Datasheet(HTML) 5 Page - Ramtron International Corporation

  FM31T372-G Datasheet HTML 1Page - Ramtron International Corporation FM31T372-G Datasheet HTML 2Page - Ramtron International Corporation FM31T372-G Datasheet HTML 3Page - Ramtron International Corporation FM31T372-G Datasheet HTML 4Page - Ramtron International Corporation FM31T372-G Datasheet HTML 5Page - Ramtron International Corporation FM31T372-G Datasheet HTML 6Page - Ramtron International Corporation FM31T372-G Datasheet HTML 7Page - Ramtron International Corporation FM31T372-G Datasheet HTML 8Page - Ramtron International Corporation FM31T372-G Datasheet HTML 9Page - Ramtron International Corporation Next Button
Zoom Inzoom in Zoom Outzoom out
 5 / 26 page
background image
FM31T372/374/376/378-G
Rev. 1.1
Apr. 2011
Page 5 of 26
The bits VTP1 and VTP0 control the trip point of the
low voltage detect circuit. They are located in register
0Bh, bits 1 and 0.
VTP
VTP1
VTP0
2.6V
0 0
2.9V
0 1
3.9V
1 0
4.4V
1 1
The watchdog timer can also be used to assert the
reset signal (/RST). The watchdog is a free running
programmable timer. The period can be software
programmed from 100 ms to 3 seconds in 100 ms
increments via a 5-bit nonvolatile register. All
programmed settings are minimum values and vary
with
temperature
according
to
the
operating
specifications. The watchdog has two additional
controls associated with its operation, a watchdog
enable bit (WDE) and timer restart bits (WR). Both
the enable bit must be set and the watchdog must
timeout in order to drive /RST active. If a reset event
occurs, the timer will automatically restart on the
rising edge of the reset pulse. If WDE=0, the
watchdog timer runs but a watchdog fault will not
cause /RST to be asserted low. The WTR flag will be
set, indicating a watchdog fault. This setting is useful
during software development and the developer does
not want /RST to drive. Note that setting the
maximum timeout setting (11111b) disables the
counter to save power. The second control is a nibble
that restarts the timer preventing a reset. The timer
should be restarted after changing the timeout value.
The watchdog timeout value is located in register
0Ah, bits 4-0, and the watchdog enable is bit 7. The
watchdog is restarted by writing the pattern 1010b to
the lower nibble of register 09h. Writing this pattern
will also cause the timer to load new timeout values.
Writing other patterns to this address will not affect
its
operation.
Note
the
watchdog
timer
is
free-running. Prior to enabling it, users should restart
the timer as described above. This assures that the
full timeout period will be set immediately after
enabling. The watchdog is disabled when VDD is
below VTP. The following table summarizes the
watchdog bits. A block diagram follows.
Watchdog timeout
WDT4-0
0Ah, bits 4-0
Watchdog enable
WDE 0Ah, bit 7
Watchdog restart
WR3-0
09h, bits 3-0
Figure 3. Watchdog Timer
Manual Reset
The /RST pin is bi-directional and allows the
FM31T37x to filter and de-bounce a manual reset
switch. The /RST input detects an external low
condition and responds by driving the /RST signal
low for 100 ms.
A manual reset does not set any
flags.
Figure 4. Manual Reset
Note that an internal weak pull-up on /RST
eliminates
the
need
for
additional
external
components.
Reset Flags
In case of a reset condition, a flag will be set to
indicate the source of the reset. A low VDD reset is
indicated by the POR flag, register 09h bit 6. A
watchdog reset is indicated by the WTR flag, register
09h bit 7. Note that the flags are internally set in
response to reset sources, but they must be cleared by
the user. When the register is read, it is possible that
both flags are set if both have occurred since the user
last cleared them.
Early Power Fail Comparator
An early power fail warning can be provided to the
processor well before VDD drops out of spec. The
comparator is used to create a power fail interrupt
(NMI). This can be accomplished by connecting the
PFI pin to the unregulated power supply via a resistor
divider. An application circuit is shown below.
Timebase
Counter
Watchdog
timeout
100 ms
clock
WDE
/RST
WR3-0 = 1010b to restart
FM31T37x
Reset
Switch
RST
MCU
Switch
Behavior
RST
FM31T37x
drives
100 ms (min.)


Número de pieza similar - FM31T372-G

Fabricante ElectrónicoNo. de piezaDatasheetDescripción Electrónicos
logo
Ramtron International C...
FM31T378 RAMTRON-FM31T378 Datasheet
1Mb / 8P
   Nonvolatile F-RAM Memory Module (TWR-FRAM)
More results

Descripción similar - FM31T372-G

Fabricante ElectrónicoNo. de piezaDatasheetDescripción Electrónicos
logo
NIHON DEMPA KOGYO
NT7050BB NDK-NT7050BB Datasheet
573Kb / 1P
   Temperature Compensated Crystal Oscillator (TCXO)
5925A NDK-5925A Datasheet
78Kb / 1P
   Temperature-Compensated Crystal Oscillator (TCXO)
logo
STMicroelectronics
M41TC8025 STMICROELECTRONICS-M41TC8025 Datasheet
187Kb / 8P
   Highly accurate, temperature-compensated serial real-time clock (RTC) with embedded crystal
logo
Kyocera Kinseki Corpota...
KT2520F26000ACW18TXX KSS-KT2520F26000ACW18TXX Datasheet
224Kb / 1P
   Temperature Compensated Crystal Oscillators (TCXO)
logo
NIHON DEMPA KOGYO
5921A NDK-5921A Datasheet
91Kb / 1P
   Temperature-Compensated Crystal Oscillator (TCXO)
5936L NDK-5936L Datasheet
83Kb / 1P
   Temperature-Compensated Crystal Oscillator (TCXO)
logo
Epson Company
X1G0054410316XX EPSON-X1G0054410316XX Datasheet
519Kb / 8P
   Temperature Compensated Crystal Oscillator (TCXO)
TG-5001LA EPSON-TG-5001LA Datasheet
241Kb / 2P
   TEMPERATURE COMPENSATED CRYSTAL OSCILLATOR (VC-TCXO)
logo
Advanced XTAL Products
AXLE1000 AXTAL-AXLE1000 Datasheet
107Kb / 4P
   UHF Temperature Compensated Crystal Oscillator (TCXO)
logo
Fox Electronics
FOX789A FOX-FOX789A Datasheet
215Kb / 1P
   TCXO SMD TEMPERATURE COMPENSATED CRYSTAL OSCILLATOR
More results


Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26


Datasheet Descarga

Go To PDF Page


Enlace URL




Política de Privacidad
ALLDATASHEET.ES
¿ALLDATASHEET es útil para Ud.?  [ DONATE ] 

Todo acerca de Alldatasheet   |   Publicidad   |   Contáctenos   |   Política de Privacidad   |   Intercambio de Enlaces   |   Lista de Fabricantes
All Rights Reserved©Alldatasheet.com


Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
Russian : Alldatasheetru.com  |   Korean : Alldatasheet.co.kr  |   Spanish : Alldatasheet.es  |   French : Alldatasheet.fr  |   Italian : Alldatasheetit.com
Portuguese : Alldatasheetpt.com  |   Polish : Alldatasheet.pl  |   Vietnamese : Alldatasheet.vn
Indian : Alldatasheet.in  |   Mexican : Alldatasheet.com.mx  |   British : Alldatasheet.co.uk  |   New Zealand : Alldatasheet.co.nz
Family Site : ic2ic.com  |   icmetro.com