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Appendix A
Specifications
©
National Instruments Corporation
A-3
Power Requirement
+5 VDC (±5%)
NI 7811R......................................... 9 mA (typ), 50 mA (max)
1
NI 7813R......................................... 9 mA (typ), 50 mA (max)
+3.3 VDC (±5%)
NI 7811R......................................... 650 mA (typ), 1,000 mA (max)
2
NI 7813R......................................... 850 mA (typ), 1,350 mA (max)
To calculate the total current sourced by the digital outputs, use the
following equation:
where
j
is the number of digital outputs being used to source current.
Power available at I/O connectors ......... +4.50 to +5.25 VDC,
250 mA per I/O connector pin
Physical
Dimensions (not including connectors)
NI PXI-781
x
R ................................ 16.0 cm
×
10.0 cm
(6.3 in.
×
3.9 in.)
NI PCI-781
x
R ................................ 15.5 cm
×
10.6 cm
(6.105 in.
×
4.162 in.)
Weight
PCI-781
x
R ...................................... 112 g
PXI-781
x
R ...................................... 162 g
I/O connectors ........................................ Four 68-pin female high-density
VHDCI type
1
Does not include current drawn form the +5 V line on the I/O connectors.
2
Does not include current sourced by the digital outputs.
current sourced on channel
i
i
1
=
j
∑