Copyright © 2006, ZMD AG, Rev. 0.8, 2006-04-12

10/22

All rights reserved. The material contained herein may not be reproduced, adapted, merged, translated, stored, or used without the prior written

consent of the copyright owner. The Information furnished in this publication is preliminary and subject to changes without notice.

ZMD30011

LIN Transceiver

Datasheet

PRELIMINARY

4. Electromagnetic Compatibility and Short-circuit Immunity

Electromagnetic Emission:

The built-in slope-control adjusts the slew rates to 2 V/µs for the rising and the falling edges. As a result the

electromagnetic emission is at a minimum.

Electromagnetic Sensitivity:

The pins LIN, WAKE, VSUP and INH are equipped with protective circuits resistant to electromagnetic imission.

The ESD-protection at these pins is guaranteed for ± 8 kV (Human Body Model).

The protection against transients (test impulses 1...3 according to ISO 7637/1) is improved by the external slave- or

master-capacitors between VSUP and GND and between LIN and GND.

Short Circuit Immunity:

5. Fail-Safe-Features

Short-circuit at LIN

power dissipation – the ZMD30011 goes into the wait-mode and the transmitter switches off.

The ZMD30011 has a special circuitry implemented that protects the battery from running out of charge in the case

of a short circuit between LIN and GND. In this failure case a normal master termination (1k resistor and diode in

series between LIN and VSUP) would cause a constant current flowing through the termination resistor (even in

sleep mode). In order to use this feature the master termination resistor has to be connected to the INH pin instead

of VSUP.

A loss of power (pins GND or VSUP) has no impact to the bus line and the protocol handler. Since there are no

reverse currents from the bus the LIN transceiver can be disconnected from the power supply without influencing

the LIN bus. Pin RXD is set floating if VSUP is disconnected.

Thermal Overload

The output driver at pin LIN is protected against thermal overload conditions. If the junction temperature

TXD Disconnection

Pin TXD is equipped with an internal pull-down resistor to provide a static low if TXD is disconnected. The LIN line is

prevented from being permanently driven in dominant state by an internal timer.

EN Disconnection

Pin EN provides an internal pull-down resistor in order to force the transceiver into sleep mode in case the pin EN is

unsupplied.