X4645 Datasheet: (X4643 / X4645) CPU Supervisor





X4645 (X4643 / X4645) CPU Supervisor Datasheet

Part Number X4645
Description (X4643 / X4645) CPU Supervisor
Manufacture Xicor
Total Page 22 Pages
PDF Download Download X4645 Datasheet PDF

Features: Preliminary Information 64K X4643/5 CPU Supervisor with 64K EEPROM DESCRIPTION 8K x 8 Bit FEATURES • Selectable w atchdog timer • Low VCC detection and reset assertion —Four standard reset threshold voltages —Adjust low VCC r eset threshold voltage using special pr ogramming sequence —Reset signal vali d to VCC = 1V • Low power CMOS —<20 µA max standby current, watchdog on <1µA standby current, watchdog off 3mA active current • 64Kbits of EEPR OM —64-byte page write mode —Self-t imed write cycle —5ms write cycle tim e (typical) • Built-in inadvertent wr ite protection —Power-up/power-down p rotection circuitry • 400kHz 2-wire i nterface • 2.7V to 5.5V power supply operation • Available packages —8-l ead SOIC —8-lead TSSOP The X4643/5 c ombines four popular functions, Power-o n Reset Control, Watchdog Timer, Supply Voltage Supervision, and Serial EEPROM Memory in one package. This combinatio n lowers system cost, reduces board space requirements, and increases reliability. Applying power to the .

Keywords: X4645, datasheet, pdf, Xicor, X4643, /, X4645, CPU, Supervisor, stock, pinout, distributor, price, schematic, inventory, databook, Electronic, Components, Parameters, parts, cross reference, chip, Semiconductor, circuit, Electric, manual, substitute, Equivalent

Preliminary Information
64K X4643/5
CPU Supervisor with 64K EEPROM
8K x 8 Bit
FEATURES
• Selectable watchdog timer
• Low VCC detection and reset assertion
—Four standard reset threshold voltages
—Adjust low VCC reset threshold voltage using
special programming sequence
—Reset signal valid to VCC = 1V
• Low power CMOS
—<20µA max standby current, watchdog on
—<1µA standby current, watchdog off
—3mA active current
• 64Kbits of EEPROM
—64-byte page write mode
—Self-timed write cycle
—5ms write cycle time (typical)
• Built-in inadvertent write protection
—Power-up/power-down protection circuitry
• 400kHz 2-wire interface
• 2.7V to 5.5V power supply operation
• Available packages
—8-lead SOIC
—8-lead TSSOP
DESCRIPTION
The X4643/5 combines four popular functions, Power-on
Reset Control, Watchdog Timer, Supply Voltage
Supervision, and Serial EEPROM Memory in one
package. This combination lowers system cost,
reduces board space requirements, and increases reli-
ability.
Applying power to the device activates the power on
reset circuit which holds RESET/RESET active for a
period of time. This allows the power supply and oscilla-
tor to stabilize before the processor can execute code.
The Watchdog Timer provides an independent protection
mechanism for microcontrollers. When the microcon-
troller fails to restart a timer within a selectable time out
interval, the device activates the RESET/RESET signal.
The user selects the interval from three preset values.
Once selected, the interval does not change, even after
cycling the power.
The device’s low VCC detection circuitry protects the
user’s system from low voltage conditions, resetting the
system when VCC falls below the set minimum VCC trip
point. RESET/RESET is asserted until VCC returns to
proper operating level and stabilizes. Four industry
BLOCK DIAGRAM
WP
SDA
SCL
S0
S1
Watchdog Transition
Detector
Data
Register
Command
Decode &
Control
Logic
VCC Threshold
Reset Logic
Protect Logic
Status
Register
EEPROM Array
VCC
VTRIP
+
-
Watchdog
Timer Reset
Reset &
Watchdog
Timebase
Power on and
Low Voltage
Reset
Generation
RESET (X4643/5)
RESET (X4645)
REV 1.26 4/30/02
www.xicor.com
Characteristics subject to change without notice. 1 of 22
Free Datasheet http://www.datasheet4u.com/

                    
                    






Index : 0  1  2  3   4  5  6  7   8  9  A  B   C  D  E  F   G  H  I  J   K  L  M  N   O  P  Q  R   S  T  U  V   W  X  Y  Z
@ 2014 :: Datasheetspdf.com :: Semiconductors datasheet search & download site (Privacy Policy & Contact)