Omega Engineering DAQ-12 user manual Channel Bipolar, Gain =

Page 15

The D/A converter channels may also be operated in unipolar mode: 0 to +5 volts, or bipolar

mode: -5 to +5 volts. The output mode is selected using jumper J5 as shown in Figure 2-5. In addition, a gain selection jumper is provided to select an output gain of 1 or 2. When using an external voltage reference, this gain can be used to amplify the D/A output for small reference voltages.

WARNING: When the internal voltage reference is used,the D/A gain MUST be set to the

gain = 1 position.

5 6 7 8

J5

1 2 3 4

Channel 0 select

Channel 0 gain

Channel 1 gain

Channel 1 select

Figure 2-5. Jumper J5 Configuration

Table 2-3 lists configuration options for jumper J5.

 

 

Channel 0

Channel 1

 

 

 

 

 

Bipolar

connect 1-5

connect 3-7

 

 

 

Unipolar

open 1-5

open 3-7

 

 

Gain = 1

connect 2-6

connect 4-8

 

 

 

Gain = 2

open 2-6

open 4-8

 

 

 

 

 

 

 

Table 2-3. D/A Converter Mode Selection Options

When configured for unipolar operation, the output voltage can be calculated from the equation:

Aout = Vref *

For bipolar operation, the equation becomes:

CODE

4096

* gain

Aout =

CODE

2048

- 1 * Vref * gain

DAQ-12 Users Manual

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Contents 15,1*,1 WARRANTY/DISCLAIMER Standards to which Conformity is Declared Manufacturers NameManufacturer’s Address Application of Council DirectiveServicing North America For immediate technical or application assistanceServicing Europe Page Table of Contents Introduction List of Figures and Tables Installation DAQ-12 Specifications Analog to Digital Converter Jumper J1 ConfigurationDisable Pre-Scaler Enable Pre-Scaler Factory default Recommended Input Ranges and Gain Settings Code Voltage Unipolar Bipolar Code Digital to Analog ConvertersGain = Channel BipolarBase Address Digital Input/OutputClock Selection Internal Clock External Clock Start of Conversion Trigger Selection10. Jumpers J8 and J9 Configuration Dack Direct Memory AccessExternal Interrupt InterruptsExternal Connections Page Control Word Register Register DescriptionINT2 INT1 INT0 Description 3 A/D Converter Data Register Start of Conversion RegisterClock Rate Register low word Multi-Function Timer Register4 D/A Converter 0 Register 5 D/A Converter 1 RegisterProgramming the 8254 Counter/Timer Counter 1 Clock rate register high word Version January 28