©Sealevel Systems, Inc.
SL9049 - 06/2011
SeaI/O Manual
20
The SeaI/O-463 offers 96 bits of buffered drive TTL I/O via four internal industry-standard 50-
pin header connectors. The interface module addresses the 96 channels of I/O as 12 eight-bit
ports, each programmable as input or output. Using standard 50-pin IDC ribbon cables, connect
up to four industry standard relay racks for PC based control and automation of equipment
including sensors, switches, security control systems, and other industrial automation systems.
A metal strain relief bracket is included to secure the cables after installation.
The SeaI/O-463 uses 74ABT245 octal bi-directional transceivers to provide TTL input/output
capabilities and can sink 64mA and source 32mA. Each bit is pulled to +5V through a 10K ohm
pull-up resistor to insure each bit is at a known state when not driven.
Power Requirements
Max Output Power
+5VDC @ 1A (5W)
Inputs
Logic High
Max 0.8VDC
Logic Low
Min 2VDC
Outputs *
Logic High
Max 0.5VDC @ 64mA
Logic Low
Min 2VDC @ 32mA
The SeaI/O-463 modules are designed to work with industry standard solid-state relay racks
that expect negative logic to operate. The SeaI/O-463 modules expect negative logic on the
inputs.
