Chapter 4 Connecting Signals© National Instruments Corporation 4-27 NI 6013/6014 User ManualCONVERT* SignalAny PFI pin can externally input the CONVERT* signal, which isavailable as an output on the PFI2/CONVERT* pin.Refer to Figures 4-11 and 4-12 for the relationship of CONVERT* tothe DAQ sequence.As an input, CONVERT* is configured in the edge-detection mode.You can select any PFI pin as the source for CONVERT* and configurethe polarity selection for either rising or falling edge. The selected edge ofCONVERT* initiates an A/D conversion.The ADC switches to hold mode within 60 ns of the selected edge. Thishold-mode delay time is a function of temperature and does not vary fromone conversion to the next. CONVERT* pulses should be separated by atleast 5 μs (200 kHz sample rate).As an output, CONVERT* reflects the actual convert pulse that isconnected to the ADC, even if the conversions are being externallygenerated by another PFI. The output is an active low pulse with a pulsewidth of 50 to 150 ns. This output is set to high-impedance at startup.Figures 4-19 and 4-20 show the input and output timing requirements forCONVERT*.Figure 4-19. CONVERT* Input Signal TimingRising-EdgePolarityFalling-EdgePolaritytw = 10 ns minimumtw
