External Reference Sources

For 625X M Series devices, you can use APFI 0 or APFI 1 for analog output external reference sources. For 628X M Series devices, you can use ao0 through ao3. On some other STC-based devices, you can use EXTREF as the analog output external reference source. Using an external voltage reference enables you to maximize the resolution of your device. If the voltages you want to generate do not exceed a certain level and you can supply an external reference voltage at that level, you achieve your device's maximum resolution. You also can use external reference voltages to apply a gain to a DC voltage or to a time-varying waveform.

Refer to the specifications for your device for additional information.