Physical Layer - CAN System Engineering - page 92

Table 2.2 Pin classes for connections of CAN transceivers
Pin classes

Characteristic features Example for pins at CAN transceivers

Global Direct connection to peripherals of

the component or only simple
filtering, respectively

CAN_H, CAN_L, VBAT, Wake

Local No direct connection to peripher-

als of the component or very
strong decoupling by filtering,
respectively

RxD, TxD, Mode, VCC

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Fig. 2.38 Test philosophy for EMC evaluation of CAN transceivers

Corresponding to this classification into EMC pin classes, only those pins of
a CAN transceiver are tested with respect to noise immunity and noise emission,
which, as global pins, feature either a direct or only a weakly decoupled connection
to peripherals of the component and thus to the connected wiring harness.

EMC Test Specification for CAN Transceivers

Figure 2.38 depicts the relation of the EMC test philosophy for CAN transceivers
according to IEC 62228 TS.
This philosophy defines the EMC measurement method for ICs as well as the
therefore-required constraints for the measurements according to the above-de-
scribed scheme. The result of the measurements according to this test specification
does not allow deriving of any generalized EMC conformance though. Only when