8

4957G–AUTO–09/09

ATA6623/ATA6625

4.3

Sleep Mode

A falling edge at EN while TXD is low switches the IC into Sleep Mode. The TXD Signal has to

be logic low during the Mode Select window (Figure 4-4 on page 8). To avoid influencing the

LIN-pin during the switch to sleep mode, it is possible to switch the EN up to 3.2 µs earlier to

LOW than the TXD. Even if the two falling edges at TXD and EN occur at the same time, the LIN

line will remain uninfluenced.

In Sleep Mode the transmission path is disabled. The supply current I

10 µA. The V

between pin LIN and pin VS is disabled, only a weak pull-up current (typically 10 µA) between

pin LIN and pin VS is present. Sleep Mode can be activated independently from the current level

on pin LIN.

A voltage less than the LIN Pre-wake detection V

receiver and switches on the internal slave termination between the LIN pin and the VS pin.

A falling edge at the LIN pin followed by a dominant bus level maintained for a certain time

period (t

device switches from Sleep Mode to Fail-safe Mode.

The V

RXD pin to interrupt the microcontroller (Figure 4-5 on page 9).

EN high can be used to switch directly from Sleep to Fail-safe Mode. If EN is still high after VCC

ramp up and undervoltage reset time, the IC switches to Normal Mode.

Figure 4-4.

Switch to Sleep Mode

Delay time sleep mode

LIN switches directly to recessive mode

LIN

VCC

NRES

TXD

EN

Sleep Mode

Normal Mode

Mode select window