TJA1021T/20/C,118 NXP Semiconductors, TJA1021T/20/C,118 Datasheet - Page 7

• Manufacturer Part Number: TJA1021T/20/C,118
• Description: IC TXRX LIN 2.1/SAE J2602 8-SOIC
• Manufacturer: NXP Semiconductors
• Type: Transceiverr

Specifications of TJA1021T/20/C,118

• Number Of Drivers/receivers: 1/1
• Protocol: LIN
• Voltage - Supply: 5.5 V ~ 27 V
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (3.9mm Width)
• Operating Supply Voltage (min): 5.5V
• Operating Temperature Classification: Automotive
• Mounting: Surface Mount
• Pin Count: 8
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 935285394118; TJA1021T/20/C-T; TJA1021T/20/C-T

NXP Semiconductors
TJA1021
Product data sheet
7.4 Normal mode
7.5 Wake-up
7.6 Remote and local wake-up
Standby mode is signalled by a LOW-level on pin RXD which can be used as an interrupt
for the microcontroller.
In Standby mode (pin SLP_N is still LOW), the condition of pin TXD (weak pull-down or
strong pull-down) indicates the wake-up source: weak pull-down for a remote wake-up
request and strong pull-down for a local wake-up request.
Setting pin SLP_N HIGH during Standby mode results in the following events:
In Normal mode the TJA1021 is able to transmit and receive data via the LIN bus line. The
receiver detects the data stream at the LIN bus input pin and transfers it via pin RXD to
the microcontroller (see
on the bus. The receiver has a supply-voltage related threshold with hysteresis and an
integrated filter to suppress bus line noise. The transmit data stream of the protocol
controller at the TXD input is converted by the transmitter into a bus signal with optimized
slew rate and wave shaping to minimize EME. The LIN bus output pin is pulled HIGH via
an internal slave termination resistor. For a master application an external resistor in
series with a diode should be connected between pin INH or V
on the other side (see
When in Sleep, Standby or Power-up mode, the TJA1021 enters Normal mode whenever
a HIGH level on pin SLP_N is maintained for a time of at least t
The TJA1021 switches to Sleep mode in case of a LOW-level on pin SLP_N, maintained
for a time of at least t
When V
Power-on mode. Though the TJA1021 is powered-up and INH is HIGH, both the
transmitter and receiver are still inactive. If SLP_N = 1 for t > t
Normal mode.
There are three ways to wake-up a TJA1021 which is in Sleep mode:
A falling edge at pin LIN followed by a LOW level maintained for a certain time period
(t
wake-up. It should be noted that the time period t
mode while TXD is HIGH, or in Sleep mode irrespective of the status of pin TXD.
1. Remote wake-up via a dominant bus state of at least t
2. Local wake-up via a negative edge at pin WAKE_N
3. Mode change (pin SLP_N is HIGH) from Sleep mode to Normal mode
wake(dom)LIN
•
•
•
An immediate reset of the wake-up source flag; thus releasing the possible strong
pull-down at pin TXD before the actual mode change (after t
A change into Normal mode if the HIGH level on pin SLP_N has been maintained for
a certain time period (t
An immediate reset of the wake-up request signal on pin RXD
BAT
exceeds the power-on-reset threshold voltage V
) and a rising edge at pin LIN respectively (see
All information provided in this document is subject to legal disclaimers.
gotosleep
Figure
Rev. 7 — 25 March 2011
Figure
gotonorm
.
7).
1): HIGH at a recessive level and LOW at a dominant level
)
wake(dom)LIN
LIN 2.1/SAE J2602 transceiver
wake(dom)LIN
Figure
th(POR)H
is measured either in Normal
gotonorm
BAT
gotonorm
gotonorm
on one side and pin LIN
4) results in a remote
, the TJA1021 enters
, the TJA1021 enters
.
TJA1021
© NXP B.V. 2011. All rights reserved.
) is performed
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