TPS3813J25_16 Datasheet, PDF (1/24 Pages) Texas Instruments – Family Processor Supervisory Circuits With Window-Watchdog

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TPS3813J25, TPS3813L30, TPS3813K33, TPS3813I50
SLVS331H – DECEMBER 2000 – REVISED JULY 2016
TPS3813xxx Family Processor Supervisory Circuits With Window-Watchdog
1 Features
•1 Window-Watchdog With Programmable Delay and
Window Ratio
• 6-Pin SOT-23 Package
• Supply Current of 9 µA (Typical)
• Power-On Reset Generator With a Fixed Delay
Time of 25 ms
• Precision Supply Voltage Monitor: 2.5 V, 3 V, 3.3
V, and 5 V
• Open-Drain Reset Output
• Temperature Range: –40°C to 85°C
2 Applications
• Applications Using DSPs, Microcontrollers, or
Microprocessors
• Safety Critical Systems
• Automotive Systems
• Heating Systems
Typical Operating Circuit
V_DD
0.1 µF
R
0.1 µF
V_DD
WDR
RESET
TPS3813
WDT
WDI
C_WP
GND
V_DD
RESET
µC
I/O
GND
Copyright © 2016, Texas Instruments Incorporated
3 Description
The TPS3813xxx family of supervisory circuits
provide circuit initialization and timing supervision,
primarily for DSPs and processor-based systems.
During power on, RESET is asserted when supply
voltage (V_DD) becomes higher than 1.1 V. Thereafter,
the supervisory circuit monitors V_DD and keeps
RESET 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, t_d = 25
ms typical, starts after V_DD has risen above the
threshold voltage (V_IT). When the supply voltage
drops below the threshold voltage (V_IT), the output
becomes active (low) again. No external components
are required. All the devices of this family have a
fixed-sense threshold voltage (V_IT) set by an internal
voltage divider.
For safety critical applications the TPS3813xxx family
incorporates a so-called window-watchdog with
programmable delay and window ratio. The upper
limit of the watchdog time-out can be set by either
connecting WDT to GND, V_DD, or using an external
capacitor. The lower limit and thus the window ratio is
set by connecting WDR to GND or V_DD. The
supervised processor now needs to trigger the
TPS3813xxx within this window not to assert a
RESET.
The product spectrum is designed for supply voltages
of 2.5 V, 3 V, 3.3 V, and 5 V. The circuits are
available in a 6-pin SOT-23 package.
The TPS3813xxx devices are characterized for
operation over a temperature range of –40°C to 85°C.
Device Information⁽¹⁾
PART NUMBER
PACKAGE
BODY SIZE (NOM)
TPS3813xxx
SOT-23 (6)
2.90 mm × 1.60 mm
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
1
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.