OM-USB-1208HS Series User's Guide
Specifications
21
Power
Table 12. Power specifications
Parameter
Condition
Specification
Operating modes
Bus-powered, USB 5 V supply
Supply current
(see Note 1)
Suspend mode
<2.5 mA
Enumeration
<100 mA
Run mode
<500 mA
Power consumption
excluding analog and
digital outputs
Run mode
OM-USB-1208HS:
1.05 W max (210 mA input current)
OM-USB-1208HS-2AO:
1.125 W max (225 mA input current)
OM-USB-1208HS-4AO:
1.175 W max (235 mA input current)
Power available for +5 V,
AICKO, AOCKO, TMR,
analog outputs, and
digital I/O
Run mode
OM-USB-1208HS:
1.45 W max
OM-USB-1208HS-2AO:
1.375 W max
OM-USB-1208HS-4AO: 1.325 W max
The total power consumption for all external loads must be less than this
value, and each load must meet the individual specification for the
terminal.
Digital output power
calculation
Power per output = Iout × 5 V
(for example, @ 24 mA, P = 0.024 × 5 = 120 mW / output)
Analog output power
calculation
(OM-USB-1208HS-2AO/
OM-USB-1208HS-4AO)
Power per output = (Iout × 16.5 V) / 0.78
(for example, @ 3 mA, P = (0.003 × 16.5) / 0.80 = 63.5 mW/output)
+5 V output power
calculation
Power (W) = Iout × 5 V
+5 V output voltage
range (see Note 2)
Run mode
4.25 V min, 5.25 V max
Suspend mode,
enumeration
0 V
+5 V output current
Run mode, no
other output loads
OM-USB-1208HS:
290 mA max (1.45 W)
OM-USB-1208HS-2AO:
275 mA max (1.375 W)
OM-USB-1208HS-4AO: 265 mA max (1.325 W)
Fuses
On USB supply
0452.750 - Littelfuse 0.750A NANO2® Slo-Blo®
Mount Fuse.
Spare fuse mounted in holder on PCB.
Note 1:
This is the total current consumption for OM-USB-1208HS Series hardware, inc5 V, digital
output and analog output currents (if supported).
Note 2:
Output voltage range assumes input power is within specified limits.
USB specifications
Table 13. USB specifications
Parameter
Specification
USB device type
USB 2.0 (high-speed)
USB device compatibility
USB 1.1, 2.0
USB cable length
5 m (16.40 ft) max
USB cable type
A-B cable, UL type AWM 2725 or equivalent (min 24 AWG VBUS/GND,
min 28 AWG D+/D–).
