Texas Instruments TPS3809, Руководство пользователя

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EVM Setup
7 SPRUI96 – October 2016
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Copyright © 2016, Texas Instruments Incorporated
TPS3813xxxQ1EVM for Processor Voltage Supervisor With Window-
Watchdog User’s Guide
The descriptions for the jumpers onboard the TPS3813xxQ1EVM are in Table 3 . The three pin jumpers
control the two settings of the WDR pin, and two of the three settings of the WDT pin. The two pin jumpers
are for the option of pulling the RESETN pin up to V
DD
and for pulling the WDT pin to GND. The RESETN
pin is an open drain, so it needs to be pulled high to assert an active low output. The WDT and WDR pins
control the length of the programmable watchdog window and the length of the lower boundary prior to the
watchdog window. The capacitor onboard the EVM is set to give a midpoint between the smallest and
largest settings of this window. A
Window Watchdog Calculator is provided for sizing the programmable
watchdog window, use the link to go to the folder to download. For more information regarding the
operation and functionality of the window-watchdog feature, refer to the
TPS3813-Q1 datasheet.
Table 3. EVM Onboard Jumpers
Jumper Device
Setting (On, VDD,
GND, or C2)
Description
J1 TPS3813K33 On Pulls RESET pin to supply voltage VDD.
J4 TPS3813K33 On Pulls the WDT pin low, lowest lower window
boundary and window.
J5 TPS3813I50 On Pulls RESET pin to supply voltage VDD.
J8 TPS3813I50 On Pulls the WDT pin low, lowest lower window
boundary and window.
J2 TPS3813K33 GND Pulls the WDR pin low, smaller lower window
boundary and window.
VDD Pulls the WDR pin high, larger lower window
boundary and window.
J3 TPS3813K33 C
ext
Applies external capacitor to the WDT pin for
programmable window.
V
DD
Pulls WDT pin high, largest lower window
boundaries and frames.
J6 TPS3813I50 GND Pulls the WDR pin low, smaller lower window
boundary and window.
V
DD
Pulls the WDR pin high, larger lower window
boundary and window.
J7 TPS3813I50 C
ext
Applies external capacitor to the WDT pin for
programmable window.
V
DD
Pulls WDT pin high, largest lower window
boundary and window.
Table 4 includes abridged EVM electrical characteristics. For a full functional description of the TPS3813-
Q1 device, refer to the TPS3813-Q1 datasheet.
Table 4. EVM Electrical Characteristics
PARAMETER CONDITION DEVICE MIN TYP MAX UNIT
Supply Voltage, VDD J2 Both 2 — 6 V
Negative-going input threshold
voltage, VIT
J2
TPS3813K33 2.87 2.93 3 V
TPS3813I50 4.45 4.55 4.65 V
3 EVM Setup
The EVM setup section details what test equipment the user needs to evaluate the EVM and how to
properly setup the EVM environment. The user should read the
TPS3813Q1 Datasheet before using the
EVM.