User`s guide

Operation Theory • 21
4
Operation Theory
In this chapter, the operation theory of the 6208 series cards is described.
Before programming or applying the 6208 series cards to your applications,
please go through this chapter to understand the features of the functions.
4.1 Voltage Output
The DA converter used in the cPCI/PCI-6208 is a Burr-Brown PCM-56U.
The DAC has a 16-bit resolution with bi-polar output. The voltage output
range is +/-10V. Therefore, the data registers are all 16-bits sign values.
The digital value ranges from -32768 (0X8000) to +32767 (0x7FFF)
corresponding to -10 Volt to +10 Volt. Table 2 shows the relation between
the digital value and the analog output voltage.
Digital Value HEX value Output Voltage
32767 0x7FFF +9.99969V
16384 0x4000 +5.00000V
8192 0x2000 +2.50000V
1 0x0001 0.00031V
0 0x0000 0.00000V
-1 0xFFFF -0.00031V
-8192 0xE000 -2.50000V
-16384 0xC000 -5.00000V
-32767 0x8001 -9.99969V
-32768 0x8000 -10.00000V
Table 2. Digital Value Vs Analog output voltage