Measurement Computing USB-1024HLS - Manual (Page 18)

USB-1024HLS User's Guide Specifications
Counter section
Table 2. Counter specifications
Pin name (Note 4) CTR
Counter type Event counter
Number of channels 1
Input source CTR screw terminal
Input type TTL, rising edge triggered
Resolution 32 bits
Schmidt trigger hysteresis 20 mV to 100 mV
Input leakage current ±1 µA
Maximum input frequency 1 MHz
High pulse width 500 ns min
Low pulse width 500 ns min
Input low voltage 0 V min, 1.0 V max
Input high voltage 4.0 V min, 15.0 V max
Note 4: CTR is a Schmitt trigger input
Power
Table 3. Power specifications
Parameter Conditions Specification
Supply current (Note 5)
No load 80mA typ, 135 mA max
Input power requirements (Note 6) 4.75 V min, 5.25 V max
USB +5 V power available Measured at "USB +5 V" screw
terminals (pins 10, 14, and 30) 4.4 V min, 5.25 V max
USB +5 V power
output current (Note 7) Connected to:
!
Self-powered hub
! Externally-powered root port hub
[350 mA] – [total output source
current]
Hold current: 350 mA, typical
Trip current: 700 mA typical
Trip/recovery time: 100 mS, max USB +5 V over-current protection Resettable fuse
On resistance: 1.3 Ohms max
Note 5:
Note 6:
Note 7:
This is the total (no load) current requirement for the USB-1024HLS.
Bus-powered hubs are allowed to provide downstream USB power as low as 4.4 V. Although your
USB-1024HLS will typically function at this 4.4 V minimum, guaranteed performance requires a
minimum power supply voltage of 4.75 V. All self-powered and root port hubs will meet this 4.75 V
minimum.
See available source/sink current level in the "Digital input/output" section.
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