Quatech RS-422 - Manual (Page 38)

9 Specifications
Bus interface: PCI, 32-bit bus, 5-volt only
IBM-compatible computers
Dimensions: approx. 5.5" x 3.5"
Serial ports
Controller: 16550 with 16-byte FIFOs
(16750 with 64-byte FIFOs optional)
Interface: Two female D-9 connectors
Transceivers: SP491 or compatible
Differential output: 2V min. with 50-ohm load (RS-422)
1.5V min. with 27-ohm load (RS-485)
Output rise/fall time: 3ns min., 40ns max., 15ns typ.
Differential input
threshold:
-0.2V min., +0.2V max.
Input resistance: 12k ohm min., 15k ohm typ.
Input current: +/- 1.0mA max.
Power requirements
+5 volts: approx. 320 mA
Temperature: operating 0° to 70°
storage -50° to 80°
Humidity: 10% to 90%
DSCLP-200/300 User's Manual 33