Measurement Computing USB-PDISO8 - Manual (Page 20)

USB-PDISO8 User's Guide Specifications
Power
Table 3. Power specifications
Parameter Conditions Specification
USB +5 V input voltage range
4.75 V min. to
5.25 V max.
USB +5 V supply current All modes of operation 10 mA max
External power input 9 V nominal
External power supply (required) MCC p/n CB-PWR-9 9 V ±10% @ 1 A
6.5 V > Vext or Vext > 12.5 V (Note 1) PWR LED = Off
(power fault)
Voltage supervisor limits - PWR LED.
6.5 V ≤ V
ext
< 12.5 V PWR LED = On
All relays on, 100 mA downstream hub power 820 mA typ, 900 mA max External power consumption
All relays off, 0 A downstream hub power 200 mA typ, 230 mA max
Note 1: The USB-PDISO8 monitors the external +9 V power supply voltage with a voltage supervisory
circuit. If this power supply exceeds its specified limit, the PWR LED will turn off, indicating a
power fault condition.
External power output
Table 4. External power output specifications
Parameter Conditions Specification
External power output - current range Note 2 4.0 A max.
External power output Voltage drop between power input and
daisy chain power output
0.5 V max
Compatible cable(s) for daisy chain C-MAPWR-x X= 2 ,3 or 6 feet
Note 2: The daisy chain power output option allows multiple Measurement Computing USB Series
products with a USB hub output port to be powered from a single external power source in a
daisy chain fashion. The voltage drop between the module power supply input and the daisy
chain output is 0.5 V max. Users must plan for this drop to assure the last module in the chain
will receive at least 6.5 VDC.
USB specifications
Table 5. USB specifications
USB "B" connector Input
USB device type USB 2.0 (full-speed)
Device compatibility USB 1.1, USB 2.0
USB "A" connector Downstream hub output port
Supports USB 2.0 high-speed, full-speed and low-speed operating points
USB hub type
Self-powered, 100 mA max downstream VBUS capability
Compatible products MCC USB Series products with a USB hub output port
USB cable type (upstream and downstream) A-B cable, UL type AWM 2527 or equivalent. (min 24 AWG VBUS/GND,
min 28 AWG D+/D-)
USB cable length 3 meters max.
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