National Instruments 6008 - Manual (Page 23)

© National Instruments Corporation 23 NI USB-6008/6009 User Guide and Specifications
Compatibility ......................................... TTL, LVTTL, CMOS
Absolute maximum voltage range ......... –0.5 to 5.8 V with respect to GND
Pull-up resistor ....................................... 4.7 k Ω to 5 V
Power-on state........................................ Input
Digital logic levels
External Voltage
+5 V output (200 mA maximum) .......... +5 V typical, +4.85 V minimum
+2.5 V output (1 mA maximum) ........... +2.5 V typical
+2.5 V accuracy ..................................... 0.25% max
Reference temperature drift ................... 50 ppm/°C max
Counter
Number of counters................................ 1
Resolution .............................................. 32 bits
Counter measurements ........................... Edge counting (falling-edge)
Counter direction.................................... Count up
Pull-up resistor ....................................... 4.7 k
Ω to 5 V
Maximum input frequency..................... 5 MHz
Minimum high pulse width .................... 100 ns
Minimum low pulse width ..................... 100 ns
Level Min Max Units
Input low voltage
Input high voltage
Input leakage current –0.3
2.0
—
0.8
5.8
50
V
V
μA
Output low voltage (I = 8.5 mA)
Output high voltage
Active drive (push-pull), I = –8.5 mA
Open collector (open-drain), I = –0.6 mA, nominal
Open collector (open-drain), I = –8.5 mA, with external
pull-up resistor
—
2.0
2.0
2.0
0.8
3.5
5.0
—
V
V
V
V