SEI-USB SEI to USB Adapter
- USB 1.1 device communicates at 12 Mbit/sec
- Compatible with USB 2.0 hubs and host adapters
- USB drivers are included for Windows 7 / 8
- Supports up to 15 total devices on the SEI bus
- Supports SEI bus lengths up to 1,000 feet, depending on the number of devices attached.
- USB port on the PC provides power for the SEI-USB and SEI bus devices (120mA max using USB port power).
- Short-circuit power protection between the USB port and the SEI bus.
- Includes two LED indicators: green for USB power-sense and red to indicate additional external power is required.
See more info below
Configure the SEI-USB
SEI-USB Product Description
The SEI-USB is an interface module that connects US Digital's SEI compatible devices to a standard USB 1.1 / 2.0 port.
The SEI (Serial Encoder Interface) bus is a network that connects up to 15 addressable SEI devices using a single 6-wire telephone-type cable up to 1000 feet long. The SEI bus uses two differential signalling pairs, one for busy flow control, and the other for bi-directional serial data (see the SEI data sheet).
The SEI-USB will supply power from the USB port to a number of SEI devices on the bus (for example, five A2 encoders at a distance of 250 feet). The SEI-USB limits the power to the maximum design spec of the USB port. A red LED, next to the SEI connector, will be lit when additional power is required and the PS-12 power supply should then be used. A green LED, next to the USB connector, is lit when the USB connection is established with the host.
View here or download the specifications
|Electrostatic Discharge, USB pins||± 15||kV
Human Body Model
|Parameter||Min.||Typ.||Max.||Units||Port / Pin||Notes|
|External Supply Voltage (optional)||8.5||12||16.0||V||J3||The external supply is used when the USB port power (J1) is not adequate to provide sufficient power when a large number of SEI devices are connected to the SEI-USB.|
|External Supply Current (optional)||-||-||1500||mA||J3||-|
|SEI-USB PWR Pin Voltage||8.0||9.5||10.5||V||P1 / 4||Generated by the SEI-USB using the USB port power (J1). Assumes that the USB PWR pin is not in a current limit mode as indicated by the red power-fault LED.|
|SEI-USB PWR Pin Current||-||-||120||mA||P1 / 4||Adequate to directly power five A2 encoders at a distance of 250 feet.|
|USB Port PWR Current, No Devices||<0.5||17||20||mA||J1 / 1||SEI-USB device load only, no devices attached.|
|USB Port PWR Current, 5 A2 Devices||-||275||480||mA||-||With 5 A2 devices attached.|
|Differential SEI Output Voltage||2.0||3.2||5.0||V||P1 / 5, 6||-|
|Differential SEI Input Voltage||0.2||-||5.0||V||P1 / 2, 3 and P1 / 5, 6||-|
|Common-mode SEI Output Voltage||2.0||2.5||3.0||V||P1 / 5, 6||-|
|Common-mode SEI Input Voltage||-4.5||-||3.0||V||P1 / 2, 3 and P1 / 5, 6||-|
|SEI Input Current (In=0-5V)||-15||-||15||mA||P1 / 2, 3 and P1 / 5, 6||-|
|Parameter||Min.||Typ.||Max.||Units||Port / Pin||Notes|
|Data Rate||1.2||-||115.2||kBaud||P1 / 5, 6||Virtual COM port speed.|
Data Latency: The USB data latency timer is preset to a default value of 16ms by the driver manufacturer. This means that data could be sitting in the FIFO buffer up to 16ms before it is forced to transmit. If Windows is allowed to search the internet for the device drivers when the "Found New Hardware" wizard is displayed, then the latency timer will be set to 16ms. The latency timer can be set to a minimum of 1ms using USBSpeedBoost software found on the US Digital website.
SEI Port (P1)
|1||GND||Ground, common for power, data and busy pairs|
|2||Busy+||Differential input line, active high, has 330 Ω pull down|
|3||Busy-||Differential input line, active low, has 330 Ω pull up|
|4||PWR||Power supply output to encoder bus (USB or external)|
|5||Data L||Bidirectional differential data line, has 330 Ω pull up|
|6||Data H||Bidirectional differential data line, has 330 Ω pull down|
Product Change Notifications
|PCN 1011||9/21/2011||The AD2B, AD4B, AD7, EADAPT, EDAC2, EDIVIDE, EPOT, EQUAD, ESUM, ESWITCH, ETACH2, SEI-USB, USB-232 currently utilizes a printed thermal transfer label. This label will no longer be used and will be replaced by laser marking directly onto the housing of the product. The purpose for this change is to create a more durable solution, and eliminate the possibility of the label being inadvertently removed from the housing.||Download|
|PCN 4464 - CE - RoHS||6/30/2014||
US Digital is aware of the increasing attention to world-wide environmental regulations, specifically with regard to the need for hazardous substance restrictions in electronic components and systems. As of July 10th, 2014 US Digital will now be CE Marking certain products inline with compliance under RoHS Directive (2011/65/EU). In order to achieve RoHS Compliance, the products will not contain more than the acceptable levels of the listed restricted substances within the RoHS 2011/65/EU directive.
Part Numbers Affected:
For the part numbers listed above, US Digital cannot confirm that they meet Low-Voltage and EMC Directives and for that reason US Digital cannot support shipping those products / product families into the CE required countries (For Example countries in the EU). Those products can still be shipped to Non-CE required countries with a Statement of Material Conformance to the RoHS Directive 2011/65/EU, in place of a RoHS Compliance Declaration.
|PCN 5514||10/7/2015||US Digital is changing the case color and label type of the SEI-USB. This change does not affect form, fit or function.||Download|
- US Digital® warrants its products against defects in materials and workmanship for two years. See complete warranty for details.
3D Model Downloads
Please configure your product first to download a 3D model.
(Note: The formats below will become links if there are 3D models available.)
- SolidWorks format
- IGES format
- Parasolid format
- STEP format
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