Output Connection; Power Supply; Figure 4-4. External Triggering - National Instruments SC-2040 User Manual

Theory of Operation Chapter 4
Differential Channel Input
PFI2 (external trigger)
PFI7 (track*/hold)
track
hold hold track
SC-2040 Channel Output
t
t
DAQ Conversion
DAQ Conversion
(DAQ board is scanning)

Figure 4-4. External Triggering

Output Connection

The output of every channel is connected to the 68-pin rear signal connector and the 50-pin
supplemental I/O connector. The 68-pin connector carries signals to and from the DAQ board,
and also provides +5 V power if selected by the power switch. The corresponding pins of the
50-pin connector are tied to those of the 68-pin connector so that you can monitor these signals
on the 50-pin connector. The pin connections of these connectors are given in Chapter 3, Signal
Connections.

Power Supply

The SC-2040 contains an onboard power switch to either power the SC-2040 from the MIO-16E
board or to draw power from an external +5 V supply. From the +5 V power, an onboard
DC-to-DC converter generates a 15 V source, which is used to power the analog circuitry. A
red LED indicates that the board is receiving power.
SC-2040 User Manual 4-6 © National Instruments Corporation