SP505 是一个单芯片器件，支持DTE到DCE连接的8种常见串行接口标准。SP505 由低功耗BiCMOS处理技术制造而成，包含一个Exar已取得专利（5,306,954）的电荷泵，允许+5V的单电源操作。可以随时通过软件为上述任何接口模式对7个驱动器和7个接收器进行配置。SP505 不需要为符合所有8种模式的操作而另外使用任何外部元件。它内部集成了所有必需的终端，这些终端在V.35驱动器、V.35接收器和V.11接收器被使用时可以被转接。SP505 可以作为DTE或DCE来操作.
SP505 还包括内部回送在内的一些其它特性，内部回送可以在单端或差分模式被启动。在回送模式中，驱动器输出在内部与接收器输入相连，建立一个内部信号通路以方便诊断测试。不再需要使用外部回送连接插头。SP505 还包括一个带有驱动器和接收器地址译码器的锁存使能管脚。驱动器和接收器输出的三态功能通过向地址译码器提供一个4位的字来控制。SP505的7个驱动器和1个接收器具有独立的使能管脚，使用起来更加方便。SP505 极其适合用在路由器、交换机、DSU/CSU和其它接入设备等网络设备的WAN串口中。
The SP505 is a monolithic device that supports eight (8) popular serial interface standards for DTE to DCE connectivity. The SP505 is fabricated using a low power BiCMOS process technology, and incorporates a Exar patented (5,306,954) charge pump allowing +5V only operation. Seven (7) drivers and seven (7) receivers can be configured via software for any of the above interface modes at any time. The SP505 requires no additional external components for compliant operation for all of the eight (8) modes of operation. All necessary termination is integrated within the SP505 and is switchable when V.35 drivers, V.35 receivers, and V.11 receivers are used. The SP505 can operate as either a DTE or DCE.
Additional features with the SP505 include internal loopback that can be initiated in either single-ended or differential modes. While in loopback mode, driver outputs are internally connected to receiver inputs creating an internal signal path convenient for diagnostic testing. This eliminates the need for an external loopback plug. The SP505 also includes a latch enable pin with the driver and receiver address decoder. Tri-state ability for the driver and receiver outputs is controlled by supplying a 4-bit word into the address decoder. Seven (7) drivers and one (1) receiver in the SP505 include separate enable pins for added convenience. The SP505 is ideal for WAN serial ports in networking equipment such as routers,switches, DSU/CSU's, and other access devices.
