®
X45620
Data Sheet
July 29, 2005
FN8250.0
Dual Voltage Monitor with Integrated
System Battery Switch and EEPROM
FEATURES
• Dual voltage monitoring
• Active low reset outputs
• Two standard reset threshold voltages
—Factory programmable threshold
• Lowline Output — zero delayed POR
• Reset signal valid to V
CC
= 1V
• System battery switch-over circuitry
• Selectable watchdog timer
—(0.15s, 0.4s, 0.8s, off)
• 256Kbits of EEPROM
• Built-in inadvertent write protection
—Power-up/power-down protection circuitry
—Protect 0, 1/4, 1/2 or all of EEPROM array with
programmable Block Lock
™
protection
—In circuit programmable ROM mode
• Minimize EEPROM programming time
—64 byte page write mode
—Self-timed write cycle
—5ms write cycle time (typical)
• 400kHz 2-wire Interface
BLOCK DIAGRAM
•
•
•
•
2.7V to 5.5V power supply operation
Available package — 20-lead TSSOP
Dual supervisor
Battery switch and output
DESCRIPTION
The Intersil X45620 combines power-on reset control,
battery switch circuit, watchdog timer, supply voltage
supervision, secondary voltage supervision, block lock
protect and serial EEPROM in one package. This
combination lowers system cost, reduces board space
requirements, and increases reliability.
Applying power to the device activates the power-on
reset circuit which holds RESET active for a period of
time. This allows the power supply and oscillator to
stabilize before the processor can execute code.
A system battery switch circuit compares V
CC
(V1MON)
with V
BATT
input and connects V
OUT
to whichever is
higher. This provides voltage to external SRAM or other
circuits in the event of main power failure. The X45620
can drive 50mA from V
CC
and 250µA from V
BATT
. The
device switches to V
BATT
when V
CC
drops below the
low V
CC
voltage threshold and V
BATT >
V
CC
.
V
OUT
V2MON
V2 Monitor
Logic
+
V2FAIL
V
TRIP2
-
WDO
Watchdog Transition
Detector
WP
Data
Register
Address-Decoder
Protect Logic
Status
Register
EEPROM
Array
Reset &
Watchdog
Timebase
BATT-ON
Watchdog
Timer Reset
SDA
SCL
Command
Decode, Test
& Control
Logic
512 X 512
(32K X 8 Bit)
S0
S1
Device
Select
Logic
V
OUT
Power-on,
Low Voltage
Reset
Generation
RESET/MR
V
CC
(V1MON)
V
OUT
V
BATT
System
Battery
Switch
+
V
CC
Monitor
Logic
V
TRIP1
-
LOWLINE
1
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 1-888-468-3774
|
Intersil (and design) is a registered trademark of Intersil Americas Inc.
Copyright Intersil Americas Inc. 2005. All Rights Reserved
All other trademarks mentioned are the property of their respective owners.
INTERSIL [ INTERSIL CORPORATION ]
