SLVS165E
–
APRIL 1998
–
REVISED DECEMBER 2002
2
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
description (continued)
The TPS3820/3/5/8 devices incorporate a manual reset input, MR. A low level at MR causes RESET to become
active. The TPS3824/5 devices include a high-level output RESET. TPS3820/3/4/8 have a watchdog timer that
is periodically triggered by a positive or negative transition at WDI. When the supervising system fails to retrigger
the watchdog circuit within the time-out interval, t
tout
, RESET becomes active for the time period t
d
. This event
also reinitializes the watchdog timer. Leaving WDI unconnected disables the watchdog.
In applications where the input to the WDI pin may be active (transitioning high and low) when the
TPS3820/3/4/8 is asserting RESET, the TPS3820/3/4/8 does not return to a non-reset state when the input
voltage is above Vt. If the application requires that input to WDI is active when RESET is asserted, WDI must
be decoupled from the active signal. This can be accomplished by using an N-channel FET in series with the
WDI pin, with the gate of the FET connected to the RESET output as shown in Figure 1.
WDI
RESET
TPS3824
WDI External
Figure 1
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 5-pin SOT23-5 package. The TPS382x devices are characterized for operation over a temperature range
of -40
°
C to 85
°
C.
PACKAGE INFORMATION
DEVICE NAME
TPS3820-33DBVT
TPS3820-50DBVT
TPS3823-25DBVT
TPS3823-30DBVT
TPS3823-33DBVT
TPS3823-50DBVT
TPS3824-25DBVT
TPS3824-30DBVT
TPS3824-33DBVT
TPS3824-50DBVT
TPS3825-33DBVT
TPS3825-50DBVT
TPS3828-33DBVT
TPS3828-50DBVT
The DBVT package indicates tape and reel of 250 parts.
The DBVR package indicates tape and reel of 3000 parts.
§
For other threshold voltage versions, please contact the local TI sales office.
DEVICE NAME
TPS3820-33DBVR
TPS3820-50DBVR
TPS3823-25DBVR
TPS3823-30DBVR
TPS3823-33DBVR
TPS3823-50DBVR
TPS3824-25DBVR
TPS3824-30DBVR
TPS3824-33DBVR
TPS3824-50DBVR
TPS3825-33DBVR
TPS3825-50DBVR
TPS3828-33DBVR
TPS3828-50DBVR
THRESHOLD VOLTAGE
§
MARKING
2.93 V
PDEI
4.55 V
PDDI
2.25 V
PAPI
2.63 V
PAQI
2.93 V
PARI
4.55 V
PASI
2.25 V
PATI
2.63 V
PAUI
2.93 V
PAVI
4.55 V
PAWI
2.93 V
PDGI
4.55 V
PDFI
2.93 V
PDII
4.55 V
PDHI