Microbox FlexRay
©2019 –EMCtools. All rights reserved. Subject to change (V1.2) Page 2 von 8
1. Introduction
Functional tests e.g. in automotive test-labs often require insulated FlexRay installations to
control the device under test. For this purpose special FlexRay transceivers are available. They
allow bidirectional data transmission of bus signals via fiber optic cables and can be used during
susceptibility tests at high field strength levels.
Quite often these transceivers are built into relatively big metal housings and use enhanced
filtering at the electrical FlexRay bus connectors. These filters may affect signal integrity and
may have major effect on emission tests.
Our EMCtools Microbox has been designed for emission and susceptibility tests. Using
multilayer technology and sophisticated circuit design full FlexRay compatibility and the ability
to perform tests at electromagnetic field levels of 270 V/m could be achieved. The handy plastic
housing allows tests with limited test space and a minimum of impact on the field.
The EMCtools Microbox uses standard multimode fiber optic cables and allows direct
connection to the electric FlexRay bus via SUB-D female connectors.
In combination with a second Microbox a complete optical FlexRay bus setup can easily be
arranged.
EMCtools Microbox has been tested for compatibility and works perfectly in combination with
MK Messtechnik optoFlex (see technical data).
2. EMCtools Microbox
The Microbox is built into a handy, rugged plastic housing (65x66x27mm).
Power is supplied externally e.g. by using an external battery or power -supply.
Fig. 1: Front Panel
Power on/off toggle switch
Control-LED for Power on/off status and supply voltage:
LED off when supply voltage less than 7V
Control-LED TXD and RXD bus activity
9-pin Sub-D connector for bus-connection
The Microbox is put into and is taken out of operation by using the toggle switch (Fig.1 –No.1).
An illuminated LED (Fig.1 –No.2) indicates the operating status of the Microbox.
Two red LEDs (Fig.1 –No.3) indicate the status of data transmission.
„TXD“(= transmit-data) indicates transmission of fiber optic data and „RXD“(= receive-data)
reception of fiber optic data.
The 9-pin Sub-D connector (Fig.1 –No.4) is used to connect the Microbox to the electrical
FlexRay-bus. See chapter 5 for details.
