Measurement Computing USB-2627 - Manual (Page 24)

USB-2627 User's Guide Specifications
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Timer output
Table 14. Timer output specifications
Parameter Specification
Terminal name TMR0, TMR1, TMR2, TMR3
Number of channels 4 channels
Timer type PWM output with count, period, delay, and pulse width registers
Output value Default state is idle low with pulses high, software-selectable, output invert
Input source 68-pin SCSI: TMR0 (pin 3), TMR1 (pin 37)
40-pin (J4): TMR0 (pin 33), TMR1 (pin 32)
40-pin (J5): TMR2 (pin 31), TMR3 (pin 35)
Internal clock frequency 64 MHz
Register widths 32-bit
High pulse width 10.42 ns, min
Low pulse width 10.42 ns, min
Output high voltage 4.4 V min (IOH = –50 µA)
3.76 V min (IOH = –1.0 mA)
Output low voltage 0.1 V max (IOL = 50 µA)
0.44 V max (IOL = 1.0 mA)
Output waveform Square wave
Output rate 64 MHz base rate divided by 2 32 ; software-selectable.
Memory
Table 15. Memory specifications
Parameter Specification
Data FIFO 4 kS analog input/2 kS analog output
Non-volatile memory 32 KB (30 KB firmware storage, 2 KB calibration/user data)
Power
Table 16. Power specifications
Parameter Condition Specification
Supply current (Note 4, Note 5) Quiescent current 360 mA
+VO output voltage range 4.25V to 5.25V
+VO output current 10 mA max
Note 4: This is the total quiescent current requirement for the device that includes up to 10 mA for the Status
LED. This value does not include potential loading of the DIO bits, +VO pin, or the XDACx outputs.
Note 5: USB 2.0 ports are required by USB 2.0 standards to supply 2500 mW (nominal at 5 V, 500 mA).
Self-powered hubs and externally-powered root port hubs provide up to 500 mA of current for a USB
device. Battery-powered root port hubs, such as in a laptop PC, provide 100 mA or 500 mA, depending
on the manufacturer. If your laptop is constrained to the 100 mA maximum, you need to purchase a
self-powered hub.