Datasheet

TJA1024 All information provided in this document is subject to legal disclaimers. © NXP Semiconductors N.V. 2015. All rights reserved.
Product data sheet Rev. 1 — 12 February 2015 8 of 25
NXP Semiconductors
TJA1024
Quad LIN 2.2A/SAE J2602 transceiver
radio frequency interference. To be valid, all wake-up events must be maintained for a
specific length of time (t
wake(dom)LIN
for a remote wake-up and t
gotonorm
for a wake-up via
SLPx_N). Pin RXDx is floating when a transceiver is in Sleep mode.
If a remote wake-up event (see Figure 4
) is detected on one of the LIN bus lines, the
associated transceiver switches to Standby mode. A wake-up initiated by the
microcontroller (SLPx_N HIGH for t
gotonorm
) will cause the relevant transceiver to switch to
Normal mode while the other transceivers remains in their current state.
7.2.3 Standby mode
Standby mode is an intermediate mode between Sleep and Normal modes. A transceiver
switches from Sleep mode to Standby mode in response to a LIN bus wake-up event. Pin
RXDx goes low to indicate the source of the remote wake-up to the microcontroller (LIN1,
LIN2, LIN3 or LIN4). A transceiver switches from Standby to Normal mode if the
microcontroller holds SLPx_N HIGH for t
gotonorm
.
7.2.4 Reset mode
When the voltage on V
BATx
drops below the LOW-level power-on reset threshold,
V
th(POR)L
, the associated dual transceiver block (LIN1/LIN2 and/or LIN3/LIN4) switches to
Reset mode. All input signals are ignored and all output drivers are off for the affected
transceivers. When the voltage on V
BATx
rises again above the HIGH-level power-on reset
threshold, V
th(POR)H
, the transceivers switch to Sleep mode.
[1] Both transceivers in the associated dual transceiver block enter Sleep mode after a power-on reset (e.g.
after switching on V
BATx
).
[2] The appropriate transceiver switches automatically to Standby x mode if a remote LINx wake-up event is
detected in Sleep x mode.
[3] RXDx is LOW to indicate the source of the remote wake-up request; RXDx goes HIGH in response to a
positive edge on pin SLPx_N.
[4] A positive edge on SLPx_N triggers a transition to Normal mode; the transmitter will be off if TXDx is LOW
and will be enabled as soon as TXDx goes HIGH.
Table 4. Operating modes
Mode SLPx_N RXDx Transmitter x Description
Reset x floating off all inputs ignored; all output
drivers off
Sleep x
[1]
0 floating off no wake-up request detected
Standby x
[2]
0LOW
[3]
off remote wake-up request
detected
Normal x 1 HIGH: recessive
LOW: dominant
on/off
[4]
bus signal shaping enabled