Functional description, 1 general information, 1 signal conditioning – Kontron CP372 User Manual
Page 31: 2 digital to analog converter, Functional description - 3, General information - 3, Signal conditioning - 3, Digital to analog converter - 3, Cp372 functional description

CP372
Functional Description
ID 25780, Rev. 01
© 2002 Kontron Modular Computers GmbH
Page 2 - 3
25780
.01.VC.021
121/1
11237
P R E L I M I N A R Y
2.
Functional Description
The following chapters present more detailed, board level information about the CP372 analog
output controller whereby the board components and their basic functionality are discussed in
general.
2.1
General Information
The CP372 is comprised basically of the following:
•
Signal conditioning
•
Digital to analog converter
•
Optocouplers
•
DAC ProComm controller
•
Realized in an FPGA device
•
Controls analog signal generation and provides interfacing to the CPCI bus
•
System interfaces for:
•
Analog outputs
•
Two, four channel clusters: Cluster A, Cluster B
•
One, 62-pin, female, 3-pin row, D-sub connector (CON2)
•
CompactPCI bus
•
132-pin, female, 6-pin row connector (CON1)
•
CompactPCI specification
•
Testing and program development (JTAG/ISP) connector (CON3)
•
On board memory: Capability EEPROM (CapROM)
•
Monitor and Control
•
Two each, green status LED’s for cluster activation (channels 0-3 and 4-7)
•
Cluster enable/disable control
•
Software
2.1.1
Signal Conditioning
Analog output signal conditioning is comprised of two clusters (A and B) each of the following:
•
Overvoltage Protection
•
EMI Suppression Filters (each signal line)
•
Gain and unipolar/bipolar conversion
•
Generation of analog voltage output as required
•
Generation of analog current output as required
(external source voltage (Vext) required)
•
Analog switches for range selection
2.1.2
Digital to Analog Converter
For each cluster there is one, four channel, 12-bit digital to analog converter (DAC) available.
After power on, the DAC ProComm controller automatically begins supplying each cluster DAC
with channel control signals and a serial data stream with digital output values for each cluster
channel. The actual channel digital input values are set to 0V initially and remain so until the
application software supplies new values. The DAC itself converts the digital inputs to analog