TLE7259-3

Functional Description

Data Sheet

11

Rev. 1.0, 2013-08-13

4.4

Sleep Mode

In order to reduce the current consumption the TLE7259-3 offers a Sleep mode. In Sleep mode the quiescent

current on

V

To switch the TLE7259-3 from Normal Operation mode to Sleep mode, the EN pin has to be set to “Low”.

Conversely a logical “High” on the EN pin sets the device directly back to Normal Operation mode (see Figure 4).

While the TLE7259-3 is in Sleep mode the following functions are available:

•

The output stage is disabled and the internal bus terminations are switched off (High Impedance on the pin

BUS). The internal current source on the bus pin ensures that the level on the pin BUS remains recessive and

protects the LIN network against accidental bus wake-up events.

•

The receiver stage is turned off.

•

RxD output pin is “High” if a pull-up resistor is connected to the external microcontroller supply. The TxD pin is

disabled. The logical state on the TxD pin is “Low”, due to the internal pull-down resistor.

•

The INH output is switched off and floating.

•

The bus wake-up comparator is active and will cause a transition to Stand-By mode in case of a bus wake-up

event.

•

The WK pin is active and turns the TLE7259-3 to Stand-By mode in case of a local wake-up.

•

The EN pin remains active, switching the EN pin to “High“ changes the operation mode to Normal Slope mode.

4.5

Wake-Up Events

A wake-up event changes the operation mode of the TLE7259-3 from Sleep mode to Stand-By mode. There are

3 different ways to wake-up the TLE7259-3 from Sleep mode.

•

Bus wake-up via a minimum dominant signal (

t

•

Local wake-up via a minimum dominant time (

t

•

Mode change from Sleep mode to Normal Operation mode, by setting the EN pin to logical “High”.

4.6

Bus Wake-Up via LIN bus

Figure 7

Bus Wake-Up behavior

The bus wake-up event, often called remote Wake-Up, changes the operation mode from Sleep mode to Stand-

event. The mode change to Stand-By mode becomes active with the following rising edge on the LIN bus. The

LIN BUS Signal

Sleep Mode

Stand-By Mode

INH