National Instruments 778473-02 Serial Interface Device

Part Number 778473-02 is the identifying part number for the National Instruments USB-232-2 Serial Interface Device. This device is mainly used to convert a standard USB port into 2 asynchronous serial ports. This allows a PC to communicate with serial devices directly through the USB port. The module is compatible with Microsoft Windows and appears as a standard device on the COM port.  

The 778473-02 is a 2-port device that supports the RS-232 serial standard and baud rates up to 230.4 kb/s. This module eliminates the need for null modem cables since it can operate in DCE and DTE transceiver mode with automatic transceiver detections. The 778473-02 measures (8.3 × 4.9 × 1.4 in.) in physical dimensions and weighs 375 g. Likewise, the module comes with case material composed of hard plastic with a metal baseplate. It contains a DB-9 male connector as the I/O connector and a USB Series B connector. As for the power requirement from the USB channel, the module typically draws 200 mA of current at +5 VDC supply and this can reach a maximum of 500 mA. 

The 778473-02 is recommended for use between the 0 to 70 °C temperature range at a relative humidity of 10 to 90%. On the other hand, it can be stored at a much wider range of –40 to 85 °C at a relative humidity range of 5% to 95%. Note that the device is designed for indoor use only and should be mounted inside a sealed enclosure for outdoor use. Likewise, the maximum altitude for the operation of the module is 2000 m. 

In the 778473-02, the maximum cable length for proper operation under RS-232 is a length equivalent to a capacitance of 2500 pF. Moreover, the data line ESD protection for the module, according to the human body model, is ±15 kV. The module meets the requirements of the following safety standards as electrical equipment for measurement, control, and laboratory use:  IEC 61010-1, EN 61010-1, UL 61010-1, and CSA 61010-1.