© National Instruments Corporation 21 USB-6008/6009 User Guide and Specifications
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)
Pull-up resistor.......................................4.7 kΩ to 5 V
Maximum input frequency.....................5 MHz
Minimum high pulse width....................100 ns
Minimum low pulse width..................... 100 ns
Input high voltage.................................. 2.0 V
Input low voltage................................... 0.8 V
Bus Interface
USB specification.................................. USB 2.0 full-speed
USB bus speed....................................... 12 Mb/s
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 = –8.5mA
Open collector (open-drain), I = –0.6mA, nominal
Open collector (open-drain), I = –8.5mA, with external pull-up
resistor
—
2.0
2.0
2.0
0.8
3.5
5.0
—
V
V
V
V