IP409: Digital Input/Output Module, Differential I/O

The IP409 provides 24 differential I/O channels with interrupts. Each channel is programmable as an input or an output on a bit basis, in any combination. All channels can generate change-of-state (COS), low, or high level transition interrupts.

Each channel uses a robust EIA RS-485/422A transceiver that supports bi-directional data transfer in one direction at a time (half-duplex). Differential data transmission enables reliable, high speed communication across distances of up to 4000 feet, even through noisy environments. Differential transmission nullifies the effects of ground shifts and noise signals which appear as common-mode voltages on the line.

Specifications

RS485 Transceivers

Bus common mode range: -7 to 12V.
Channel configuration: 24 independent, non-isolated RS485/422A serial ports with a common signal return connection.
Data rate: 250K bits/second, maximum.
Cable length: 4000 feet, maximum. Use of a signal repeater can extend transmission distances.
Termination resistors: 120 ohm resistors installed in board sockets at network endpoints only.
Differential output voltage: 5V,maximum. 1.5V minimum (with 27 ohm load).
Common mode output voltage: 3V, maximum.
Output short circuit current: 250mA, maximum.
Rise/fall time: 250nS, minimum, 800nS, typical. 2000nS, maximum.
Receiver input impedance: 12K ohms.

IP Compliance (ANSI/VITA 4)

Meets IP specifications per ANSI/VITA 4-1995.
IP data transfer cycle types supported: Input/output (IOSel*), ID read (IDSel*).
Access Time (8MHz clock): 0 wait states (250nS cycle).
Interrupt handling format: An 8-bit vector is provided during interrupt acknowledge cycles on D0 – D7.

Environmental

Operating temperature: 0 to 70°C (IP409) or -40 to 85°C (IP409E).
Storage temperature: -55 to 125°C (all models).
Relative Humidity: 5 to 95% non-condensing
Power:
+5V (±5%): 50mA maximum.
±12V (±5%) from P1: Not used.
MTBF: 5,258,978 hrs at 25°C, MIL-HDBK-217F, Notice 2