TPS3619-33 Datasheet, PDF (1/18 Pages) Texas Instruments – BACKUP-BATTERY SUPERVISORS FOR RAM RETENTION

TPS3619-33, TPS3619-50
TPS3620-33, TPS3620-50
www.ti.com
SLVS387G – APRIL 2001 – REVISED DECEMBER 2006
BACKUP-BATTERY SUPERVISORS FOR RAM RETENTION
FEATURES
• Supply Current of 40 µA (Max)
• Battery-Supply Current of 100 nA (Max)
• Precision Supply Voltage Monitor 3.3 V, 5 V,
Other Options on Request
• Backup-Battery Voltage Can Exceed V_DD
• Power On Reset Generator With Fixed 100-ms
Reset Delay Time
• Voltage Monitor For Power-Fail or Low-Battery
Monitoring
• Battery Freshness Seal (TPS3619)
• Pin-For-Pin Compatible With MAX819,
MAX703, and MAX704
• 8-Pin MSOP Package
• Temperature Range –40°C to +85°C
APPLICATIONS
• Fax Machines
• Set-Top Boxes
• Advanced Voice Mail Systems
• Portable Battery-Powered Equipment
• Computer Equipment
• Advanced Modems
• Automotive Systems
• Portable Long-Time Monitoring Equipment
• Point-of-Sale Equipment
DESCRIPTION
The TPS3619 and TPS3620 families of supervisory
circuits monitor and control processor activity by
providing backup-battery switchover for data
retention of CMOS RAM.
During power on, RESET is asserted when the
supply voltage (V_DD or V_BAT) becomes higher than
1.1 V. Thereafter, the supply voltage supervisor
monitors V_DD and keeps RESET output active as
long as V_DD remains below the threshold voltage
(V_IT). An internal timer delays the return of the output
to the inactive state (high) to ensure proper system
reset. The delay time starts after V_DD has risen
above V_IT. When the supply voltage drops below V_IT,
the output becomes active (low) again.
The product spectrum is designed for supply
voltages of 3.3 V and 5 V. The TPS3619 and
TPS3620 are available in an 8-pin MSOP package
and are characterized for operation over a
temperature range of –40°C to +85°C.
DGK PACKAGE
(TOP VIEW)
V_OUT
1
V_DD
2
GND
3
PFI
4
8
V_BAT
7
RESET
6
MR
ACTUAL SIZE
3,05 mm x 4,98 mm
5
PFO
Power
Supply
0.1 µF
External
Source
TYPICAL OPERATING CIRCUIT
TPS3619
TPS3620
V_DD
V_BAT
Backup
Battery
Microcontroller
or
Microprocessor
R_x
R_y
Manual
Reset
RESET
PFI
PFO
MR
V_OUT
GND
RESET
Switchover
Capacitor
0.1 µF
I/O
V_CC
GND
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Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
All trademarks are the property of their respective owners.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2001–2006, Texas Instruments Incorporated