908E624_10 Datasheet, PDF (26/40 Pages) Freescale Semiconductor, Inc – Integrated Triple High Side Switch with Embedded MCU and LIN Serial Communicationfor Relay Drivers

FUNCTIONAL DEVICE OPERATION
OPERATIONAL MODES
MODE2:1 LINSL2:1
LIN-PU
LINWU
LINFAIL
Control
VSUP1
2µA
TXD
RXD
Slope
Control
WakeUp
Filter
30k
LIN bus
GND
Figure 15. LIN Interface
TXD Terminal
The TXD terminal is the MCU interface to control the state
of the LIN transmitter (see Figure 2, page 2). When TXD is
LOW, the LIN terminal is low (dominant state). When TXD is
HIGH, the LIN output MOSFET is turned off (recessive state).
The TXD terminal has an internal pullup current source in
order to set the LIN bus to recessive state in the event, for
instance, the microcontroller could not control it during
system power-up or power-down.
RXD Terminal
The RXD transceiver terminal is the MCU interface, which
reports the state of the LIN bus voltage. LIN HIGH (recessive
state) is reported by a high level on RXD, LIN LOW (dominant
state) by a low level on RXD.
STOP Mode and Wake-up Feature
During STOP mode operation the transmitter of the
physical layer is disabled. In case the bit LIN-PU was set in
the Stop mode sequence the internal pull-up resistor is
disconnected from VSUP and a small current source keeps
the LIN terminal in recessive state. The receiver is still active
and able to detect wake-up events on the LIN bus line.
A dominant level longer than T_propWL followed by an rising
edge will generate a wake-up interrupt and set the LINWF
flag in the SPI Status Register. Also see Figure 9, page 16.
SLEEP Mode and Wake-up Feature
During SLEEP mode operation the transmitter of the
physical layer is disabled. In case the bit LIN-PU was set in
the Sleep mode sequence the internal pull-up resistor is
disconnected from VSUP and a small current source keeps
the LIN terminal in recessive state. The receiver is still active
to be able to detect wake-up events on the LIN bus line.
A dominant level longer than T_propWL followed by an rising
edge will generate a system wake-up (reset) and set the
LINWF flag in the SPI Status Register. Also see Figure 8,
page 16).
908E624
26
Analog Integrated Circuit Device Data
Freescale Semiconductor