USB-1608G User's Guide Specifications
19
External clock input/output
Table 8. External clock I/O specifications
AICKI: Input, active on rising edge
AICKO: Output, power on default is 0 V, active on rising edge
AICKI: Receives sampling clock from external source
AICKO: Outputs the internal A/D sampling clock, or the pulse generated from AICKI
when in external clock mode.
Schmitt trigger, 33 Ω series resistor, 47 kΩ pull-down to ground
Schmitt trigger hysteresis
2.2 V min
5.5 V absolute max
1.5 V max
–0.5 V absolute min
0 V recommended min
4.4 V min (IOH = –50 µA)
3.76 V min (IOH = –2.5 mA)
0.1 V max (IOL = 50 µA)
0.44 V max (IOL = 2.5 mA)
Counter
Table 9. Counter specifications
Schmitt trigger, 33 Ω series resistor, 47 kΩ pull-down to ground
CTR0 (pin 52)
CTR1 (pin 51)
Counter read/writes rates
(software paced)
33 to 8000 reads/writes per second typ, system dependent
Schmitt trigger hysteresis