VXI 6 U

The VMEbus, based on the IEEE 1014 and IEC 821 standards, has become an established industrial standard worldwide. The VXIbus (VMEbus Extensions for Instrumentation) extends the VME family based on System Specification VXI-1 Revision 3.0 from November 24, 2003. All Hartmann VMEbus boards are based on the HIGH-SPEED DESIGN concept. Low reflection is achieved by means of uniform signal line surge impedance. Shielding of each individual signal line assures minimal coupling and therefore guarantees trouble-free operation.

Termination

In order to prevent interference on signal lines which might result from reflection at open line ends, these lines must be terminated. A distinction is made between passive and active termination. The advantage of active termination is reduced closed-circuit current consumption. Passive termination features better frequency response.

Automatic daisy chaining

For this VXI-Backplane daisy chaining is implemented using a integrated OR logic. This logic closes the daisy chain when the daughter board is removed.

Chassis GND connection

There is a solid electrically conductive chassis GND surface in the backplaneto- card rack mounting area. This guarantees EMC-tight mounting of the bus board on the card rack.

HF coupling of card rack and system ground is implemented for VXI by capacitors (10 nF, 200 V in each slot). Static charges are discharged with a resistor (≥ 1 MΩ).

Chassis-GND is connected with the Backplane with a contact area. Additional its possible to make a connection over a M4-terminal.

In case of using an extended terminal bar for GND its possible to connect the chassis directly with Digital-GND. Every Slot is shielded. There are 2 variants available: One is connecting the shield with Chassis-GND and the other with Digital-GND.

Power connections

The main operating voltages and GND are supplied via terminal bars with M6 screw connections.

The auxiliary operating voltages are supplied via M4 screw terminals with dual Fastons. Optimal daughter board supply and trouble-free operation are ensured by the arrangement of the feed modules on the backplane.

Utility connector

The special signals to the power supply unit are brought out to a separate connector on the backplane. Beside the lines for voltage monitoring 8 external connectors for temperature sensors are feed-through to the 40-pin connector.

All lines for voltage monitoring are connected with line filters. A doublerow 40-pin connector with a contact spacing of 2.54 mm is used.

Power Management

There is an additional connector for IPMB on the backplane. IPMB_PWR is alternative accessible with an optional 3-pin feed-through contacts or with assembled zero-Ohm-resistors.

Pin Assignments

Pin Assignments J2