F81438G,Single 5V RS232/RS422/RS485 Multiprotocol单5V RS232 / RS422 / RS485多协议,
1 General DescriptionThe F81438 is programmable, monolithic multi-protocol transceiver device that contains RS-232and_RS-485 / RS-422 drivers and_receivers. The F81438 can be reconfigured into four operatingmodes including RS-232 only (3TX/5RX), one RS-485 (1TX/1RX) driver (TX) half duplex mode, oneRS-485 (1TX/1RX) receiver (RX) half duplex mode, and_RS-422 (1TX/1RX) full duplex mode whichcan be selected whenever you need by changing the logic state of the 2 mode selection pins. Thedevice can implement a dual-mode serial port, mixed mode ports or as an interface signal translator.The extra charge pumps deliver true RS-232 driver output voltage from a single power supply at 5V.A slew rate control pin configures driver outputs for either high data rate or slew-controlled data rates.Slew-controlled outputs minimize the problems that caused by the reflections and_ringing on long orun-terminated cables.All RS-485 receivers or transceivers feature high impedance which allow up to 256 transceiverson a shared bus. When configured in RS-485/RS-422 mode, each driver may be individually enabledor put into tri-state, simplifying use on shared buses or bidirectional communication. All receivershave advanced failsafe protection to prevent oscillation when inputs are un - connected. In RS-232mode each receiver input has a 5k?pull-down to ground. Differential Receivers will default to outputlogic 1 if inputs are floating, shorted or open but terminated. All driver outputs and_receiver inputs areprotected against ESD strikes up to ±15,000 volts (IEC 61000-4-2 Air Gap).2 Feature List5V Single Supply OperationRobust ±15kV ESD Protection (IEC 61000-4-2 Air Gap)Mixed RS-232 / RS-485 ModesAdjustable Slew Rate for Minimize EMI ErrorRS-485 Advance Failsafe on Open, Short or Terminated Lines28 Pin TSSOP PackagingFlexible 4 Operation Modes Selected by 2 Configuration PinsOne set of 3T5R RS-232 V.28 Drivers & ReceiversOne Set of RS-485 Drivers (Half Duplex Configuration)One Set of RS-485 Receivers (Half Duplex Configuration)One set of RS-422 Driver & Receiver (Full Duplex Configuration).
