7

Analog Output

Many M Series devices have analog output functionality. NI 621x devices that support analog output have two AO channels controlled by a single clock and capable of waveform generation. Refer to Appendix A, Device-Specific Information, for information about the capabilities of your device.

Figure 7-1shows the analog output circuitry of M Series devices.

Isolation

Barrier

(USB-6215

and USB-6218

devices only)

AO 0

DAC0

 

 

 

 

 

AO FIFO

 

Digital

 

AO Data

 

 

 

 

 

 

 

Isolators

 

 

 

 

 

 

 

 

 

 

 

AO 1

DAC1

 

 

 

 

 

 

 

 

 

 

AO Sample Clock

Figure 7-1.M Series Analog Output Circuitry

Analog Output Circuitry

DACs

Digital-to-analog converters (DACs) convert digital codes to analog voltages.

AO FIFO

The AO FIFO enables analog output waveform generation. It is a first-in-first-out (FIFO) memory buffer between the computer and the

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7-1

NI USB-621x User Manual