National Instruments Lab-PC+, Руководство пользователя

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Appendix A Specifications
© National Instruments Corporation A-5 Lab-PC+ User Manual
Differential nonlinearity (DNL) in a D/A system is a measure of deviation of code width from
1 LSB. In this case, code width is the difference between the analog values produced by
consecutive digital codes. A specification of
±
1 LSB differential nonlinearity ensures that the
code width is always greater than 0 LSBs (guaranteeing monotonicity) and is always less than
2 LSBs.
Digital I/O
Number of channels ...................................... 24
Compatibility ................................................ TTL
Digital logic levels ........................................
Level Min Max
Input low voltage
Input high voltage
Input low current
(V
in
= 0.8 V)
Input high current
(V
in
= 2.2 V)
-0.3 V
2.2 V
-
-
0.8 V
5.3 V
-1.0
µ
A
1.0
µ
A
Output low voltage
(I
out
= 2.5 mA)
Output high voltage
(I
out
= -2.5 mA)
-
3.7 V
0.4 V
-
Darlington drive output current (Ports B and C only)
(R
EXT
= 700
Ω
, V
EXT
= 1.7 V)................
±
2.5 mA min,
±
4 mA max
Handshaking.................................................. 3-wire (requires 1 port)
Power-on state ............................................... Configured as input
Data transfers ................................................ Interrupt, programmed I/O
Timing I/O
Number of channels ...................................... 3 counter/timers
Resolution ..................................................... 16 bits
Compatibility ................................................ TTL, gate and source pulled high with
4.7 k
Ω
resistors
Base clocks available .................................... 2 MHz
Base clock accuracy ...................................... 0.01%
Max source frequency ................................... 8 MHz
Min source pulse duration ............................. 60 ns
Min gate pulse duration................................. 50 ns
Data transfers ................................................ Programmed I/O