Data Sheet

15

Rev. 1.2, 2007-11-13

TLE7269G

Functional Description

4.8

Local Wake-Up

Figure 9

Local Wake-Up behavior

Beside the remote Wake-Up, a Wake-Up of the TLE7269G via the WK pin is possible. This type of Wake-Up event

Wake-Up (see Figure 9) and changes the operation mode to Stand-By mode.

In Stand-By mode the TxD1 pin indicates the source of the Wake-Up event, the TxD2 pin remains inactive. A

strong pull-down on the pin TxD1 indicates a bus Wake-Up event (see Figure 4). The RxD1 pin signals if a Wake-

Up event or the Power-Up event occurred. A “Low” signal on the RxD1 pin reports a local or bus Wake-Up event,

a logical “High” signal on RxD1 indicates a Power-Up event. A “Low” signal on the RxD2 pin indicates a Wake-Up

event on the pin BUS2.

4.9

Mode Transition via EN pin

Figure 10

Mode Transition via EN pin

It is also possible to change from Sleep mode to Normal Operation mode by setting the EN pin to logical

“High”.This feature is useful if the external microcontroller is continuously powered and not connected to the INH1

pin or the INH2 pin. The EN pin has an integrated pull-down resistor to ensure the device remains in Sleep or

Stand-By mode even if the voltage on the EN pin is floating. The EN pin has an integrated hysteresis to avoid the

toggling of the operation modes during the transition of the EN signal (see Figure 10).

V

WK

V

WK,L

WK Signal

Sleep Mode

Stand-By Mode

INH1/

INH2

t

WK

V

EN

EN Signal

V

EN,OFF

Sleep Mode /

Stand-By Mode

t

MODE

V

EN,ON

EN Hysteresis

Sleep Mode

Normal Operation Mode

t

MODE