RS-232/485 CONVERTER
2. Introduction
2.1 Description
The RS-232/485 Converter (IC620A) is an ultra- miniature interface converter. Requiring no
AC power or batteries for operation, the Converter supports asynchronous communication up to
115.2Kbps over one or two unconditioned twisted pairs. Distances up to 15 miles (24 km) are attainable at lower data rates (1.2 Kbps, 19 AWG twisted pair).
The Converter can handle up to 31 terminal drops in a multipoint polling environment. For RS-485 applications that require hardware handshaking, the Converter passes one control signal in each direction (see the last bullet point in Section 2.2 for an explanation). The Converter may be configured for high or low impedance, and the carrier may be set to “constantly on” or “controlled by RTS.” The unit can operate with or without “echo.” RTS/CTS delay may be set for “no delay” or “8 ms delay.”
There are three options for twisted-pair connection: terminal blocks with strain relief, RJ-11, or RJ-45. Silicon Avalanche Diodes provide 600 watts per wire of protection against harmful data-line transient surges.
