33663 datasheet(29/37 Pages) FREESCALE

29 / 37 page

Analog Integrated Circuit Device Data



Freescale Semiconductor

33663

FUNCTIONAL DEVICE OPERATION

OPERATIONAL MODES

In Sleep mode, the transmission path is disabled and the LIN Module 1 is in Low Power mode. Supply current from VSUP is

very low. Wake-up can occur from LIN1 bus activity, from the EN1 pin and from the WAKE1 input pin. If during the preparation

to Sleep mode delay (tSD), the LIN1 bus goes low due to LIN1 network communication, the LIN Module 1 still enters Sleep mode.

The LIN Module 1 can be awakened by a recessive to dominant start, followed by a dominant to recessive state after t > tWUF.

After a wake-up event, the LIN Module 1 enters into Awake mode. In Sleep mode, the LIN Module 1 internal 725 kOhm pull-

up resistor is connected and the 30 kOhm is disconnected.

DEVICE POWER-UP (Awake Transitional Mode)

At power-up (VSUP rises from zero), when VSUP is above the Power-On Reset voltage, both LIN Modules automatically switch

after a 160 µs delay time to the Awake transitional mode. Both INH pins (INH1 and INH2) go to a HIGH state and RXD1and RXD2

to a LOW state. See Figure 21.

DEVICE WAKE-UP EVENTS

The 33663L, 33663J and 33663S can be awakened from Sleep mode by three wake-up events:

• Remote wake-up via LIN1 and/or LIN2 bus activity

• Via the EN1 and/or EN2 pin

• Toggling the WAKE1 and/or WAKE2 pin

Remote Wake from LIN1, LIN2 Bus (Awake Transitional Mode)

Each LIN Transceiver is awakened by its LIN dominant pulse longer than tWUF. Dominant pulse means: a recessive to

dominant transition, wait for t > tWUF, then a dominant to recessive transition. This is illustrated in Figure 15. Once the wake-up

is detected (during the dominant to recessive transition), the LIN Module waken up by its LIN enters into Awake mode, with its

INH HIGH and RXD pulled LOW.

Once in the Awake mode, its EN pin has to be set to 3.3 V or 5.0 V (depending on the system) to enter into Normal mode.

Once in Normal mode, the LIN Module has to wait tFIRST_DOM delay before transmitting the first dominant bit.

Wake-up from EN1, EN2 pins

Each LIN Module can be awakened by a LOW to HIGH transition of its EN pin. When EN is switched from LOW to HIGH and

stays HIGH for a delay higher than tLWUE, the LIN Module is awakened and enters into Normal mode. See Figure 14. Once in

Normal mode, the LIN Module has to wait tFIRST_DOM delay before transmitting the first dominant bit.

Wake-up from WAKE1, WAKE2 Pins (Awake Transitional Mode)

Just before entering the Sleep mode, the WAKE pin state of the concerned LIN Module is stored. A change in the level longer

than the deglitcher time (70 µs maximum) will generate a wake-up, and the LIN Module enters into the Awake Transitional mode,

with its INH HIGH and RXD pulled LOW. See Figure 16. The LIN Module goes into Normal mode when its EN is switched from

LOW to HIGH and stays HIGH for a delay higher than tLWUE. Once in Normal mode, the LIN Module has to wait tFIRST_DOM delay

before transmitting the first dominant bit.

33663 Datasheet(PDF) 29 Page - Freescale Semiconductor, Inc