AD2B Product Description
The AD2B adapter allows the RS-485-like signal of SEI devices to interface to a standard RS-232 port (9-pin DB), such as those in IBM-compatible PCs. The SEI (Serial Encoder Interface) bus is a simple, quick, and convenient network of SEI devices interfacing to an RS-232 serial port. The SEI bus supports from 1 to 15 devices on a single 6-wire telephone-type cable, up to 1000 feet long. For more information on the SEI bus, please see the SEI page.
The AD2B has 2 differential signals to interface to SEI devices: the bidirectional data pair for communication and the busy input pair for data flow control. The PS-12 power supply connects to the AD2B and furnishes power for all SEI devices on the bus.
Mechanical Drawings
Specifications
ELECTRICAL
Specifications apply over entire operating temperature range.
| PARAMETER | MIN. | TYP. | MAX. | UNITS | NOTES |
|---|---|---|---|---|---|
| Supply Voltage | 8.0 | - | 16 | Volts | - |
| Supply Current (without encoders) | - | - | 15 | mA | - |
| Differential SEI Output voltage |DataL - DataH|, |Busy+ - Busy-| |
2.0 | 2.75 | 5.0 | Volts | Load = 100Ω |
| Differential SEI Input Voltage |DataL - DataH|, |Busy+ - Busy-| |
0.2 | - | 5.0 | Volts | - |
| Common Mode SEI Output Voltage (DataH + DataL)/2, (Busy- + Busy+)/2 |
2.0 | 2.5 | 3.0 | Volts | Load = 100Ω |
| Common Mode SEI Input Voltage (DataH + DataL)/2, (Busy- + Busy+)/2 |
-4.5 | - | 3.0 | Volts | - |
| Input current DataH, DataL, Busy-, Busy+ |
-15 | - | 15 | mA | In = 0 to 5V |
| RS-232 Output | ±5.0 | ±8.0 | - | Volts | - |
| RS-232 Input | ±3.5 | - | ±15 | Volts | - |
| RS-232 Input Resistance | 3 | 5 | 7 | kΩ | - |
ABSOLUTE MAXIMUM RATINGS
| PARAMETER | MIN. | MAX. | UNITS |
|---|---|---|---|
| Storage Temperature | -40 | 100 | C |
| Operating Temperature | 0 | 70 | C |
| Humidity (non-condensing) | 0 | 95 | % |
FUNCTIONAL PIN DESCRIPTIONS
MOD6:
| PIN | NAME | DESCRIPTION |
|---|---|---|
| 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. |
| 5 | DataL | Bidirectional differential data line, has 330 Ω pull up. |
| 6 | DataH | Bidirectional differential data line, has 330 Ω pull down. |
DB9F:
| PIN | NAME | DESCRIPTION |
|---|---|---|
| 3 | RXD | Data input from host, normally low. |
| 2 | TXD | Data output to host, normally low. |
| 7 | RTS | Not connected. |
| 8 | CTS | Busy line to host, active low. |
| 5 | GND | Ground, common for RS232 signals. |
CABLES & CONNECTORS
| 6-pin Modular | ||
|---|---|---|
| Cables | Description | |
| CA-MD6-SH-MD6-x | Modular connectors on both ends of a shielded cable | |
| CA-MD6-SS-MD6-x | Modular connectors on both ends of a silver satin cable | |
| Connectors | Description | |
| CON-MD6-2J | Two-way 6 conductor modular connectors | |
| CON-MD6-3J | Three-way 6 conductor modular connectors | |
Attention:
- The cables supplied for the SEI bus by US Digital are wired straight through with no crossed wires. Cables and splitters intended for telephone system usage are wired differently and may damage your SEI device.
- Specify cable length when ordering.
Configuration Options |
| AD2B |
|
PLEASE NOTE: This chart is for informational use only. Certain product configuration combinations are not available. Visit the AD2B product page for pricing and additional information. |