Kontron CP383 - Manual (Page 35)

CP383 Functional Description
ID 27784, Rev. 01 © 2004 Kontron Modular Computers GmbH Page 2 - 5
27784
.01.VC.040308/162543
P R E L I M I N A R Y
2.3 Digital Input Signal Conditioning
The digital input signal conditioning consists of the following:
• Overvoltage protection
• Low-pass signal filtering
• Current limitation
• Inverse polarity protection
• Input signal high-low determination
• Output signal stabilization buffering
2.4 Digital Output Signal Conditioning
The major element of the digital output signal conditioning is the HSD switches which are able
to drive inductive, capacitive or resistive loads. Diagnostic information for the System Master
and extensive use of electrical protection are among their main characteristics.
The HSD switch (type L6376 manufactured by SGS THOMSON) is a QUAD intelligent power
switch which adapts the digital output signals to the prevailing voltage and current levels, and
also provides corresponding mechanisms to protect against undervoltage, overcurrent and
overtemperature.
The output voltage level is adapted to the external supply voltage for high level and for low level
output voltage respectively via the integrated FET transistor output stage within the HSD
switch. The HSD switch implements a clamp diode for inductive load driving. The voltage
source for the CP383 front end is implemented using an external voltage source (nominal
+24V, also in the range +9.5V to +35V).
The input signals to the HSD switches are derived from the system side, directly from the out-
puts of the optocoupler devices.
2.5 Optoisolation
The process side is galvanically isolated from the system side. The process side of the board
is separated from the system side by a bank of optocouplers which serve to protect the system
side from any excess voltages or voltage spikes.
2.6 DIO ProComm Controller
The DIO ProComm Controller is responsible for supervising and controlling the digital acquisi-
tion and the digital data output process, and maintaining communication with the CompactPCI
System Master. Applications address the CP383 through its software driver interface within the
System Master whereby the controller accepts requests from the driver and executes them ac-
cordingly. Digital data from the signal conditioning is processed through the DIO ProComm
Controller and then made available to the System Master. Digital data from the System Master
is processed through the DIO ProComm Controller and then routed to the HSD switches.
2.7 System Interfaces
The CP383 provides interfacing capability for the following system elements:
• Front panel connector
• CompactPCI bus