Table 2-1. Pinout in Pin Mode vs. Pinout in SPI Mode
Pin
Pin mode
SPI mode
4
WDT
– Programmable watchdog window set input
CLK
– SPI clock input
5
nWDR
– Watchdog failure output trigger
SDO
– SPI serial data output
6
WDI
– Watchdog timer edge-triggered input
SDI
– SPI serial data input
7
PIN
– Input that sets the device to pin mode
nCS
– SPI chip select
8
EN
– Device mode change input
nINT
– Device interrupt output
9
HSSC
– High-side switch control input
FSO
– Function output
The user can start up the TLIN1431-Q1 into pin mode by connecting a shunt between pins “PIN/nCS” and
“GND_PD” of J5, which applies a pull-down to GND to pin 7. Leaving all pins of J5 floating results in the
TLIN1431-Q1 operating in SPI mode, and the TLIN14315-Q1 operates with 3.3 V SPI. Connect a shunt between
pins “PIN/nCS” and “VCC_PU” of J5 to apply a pull-up to VCC, resulting in 5 V SPI operation for the TLIN14315-
Q1.
2.1.2 Wake Request (WKRQ) vs. Inhibit Output (INH)
The WKRQ/INH pin has the capability of operating as either a logic-level wake request (WKRQ) digital output,
or a high-voltage inhibit (INH) output based upon its biasing at startup. Applying a 100 kΩ or stronger pull-down
to GND on this pin results in the pin behaving as logic-level WKRQ. Alternatively, leaving this pin floating or
applying a 1 MΩ pull-down to GND results in the pin behaving as high-voltage INH.
Control
V
SUP
WKRQ/
INH
V
INT
Control
V
SUP
WKRQ/
INH
V
INT
INH
GND
WKRQ
100 k
GND
1 M
Floating or 1 M
pull-
down make pin INH
Figure 2-2. WKRQ or INH Pin Select
The user can configure this pin as WKRQ by connecting a shunt between pins “U1.16” and “WKRQ” of J2
to apply a 100 kΩ pull-down. Alternatively, the user can configure the WKRQ/INH pin as high-voltage INH by
connecting a shunt between pins “U1.16” and “INH” of J2 at power-up to apply a 1 MΩ pull-down, or by leaving
all of these pins floating. In addition, capacitor pad C29 allows for the user to test a capacitor in parallel with the
1 MΩ resistor in order to evaluate the behavior of this pin at startup.
2.2 Commander and Responder Configurations
The TLIN1431-Q1 has an internal pull-up resistor and serial diode on LIN that allows it to operate as a
responder. To operate as a commander, an external 1 kΩ pull-up and serial diode is required on the bus.
The user can apply a shunt between the pins of J10 to apply this 1 kΩ pull-up and allow for use as a commander
node.
2.3 Local Wake-Up
The WAKE pin of the TLIN1431-Q1 is used for the local wake-up (LWU) function of the device, which is
explained in detail in the data sheet. This can be directly interfaced close to the device using J15, pin “WAKE”
without a shunt. Applying a shunt to J15 applies a pull-up and allows the use of the WAKE switch on the board.
EVM Setup and Features
SLLU326 – MAY 2022
TLIN1431EVM User's Guide
5
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