SP483 / SP485 Low Power Half-Duplex RS-485 Transceivers FEATURES +5V Only Low Power BiCMOS Driver / Receiver Enable Slew Rate Limited Driver for Low EMI (SP483) Low Power Shutdown mode (SP483) RS-485 and RS-422 Drivers/Receivers DESCRIPTION The SP483 and SP485 are a family of half-duplex transceivers that meet the specifications of RS-485 and RS-422. Their BiCMOS design allows low power operation without sacrificing performance. The SP485 meets the requirements of RS-485 and RS-422 up to 5Mbps. Ad- ditionally, the SP483 is equipped with a low power Shutdown mode. The SP483 is internally slew rate limited to reduce EMI and can meet the requirements of RS-485 and RS-422 up to 250kbps. Exar Corporation 48720 Kato Road, Fremont CA, 94538 50-668-70 7 www .exar.com SP483 SP485 0 0627 ABSOLUTE MAXIMUM RATINGS These are stress ratings only and functional operation of the device at these ratings or any other above those Output Voltages indicated in the operation sections of the specifications Logic.........................-0.3V to (Vcc + 0.5V) below is not implied. Exposure to absolute maximum Drivers.............................................+/-5V rating conditions for extended periods of time may Receivers..................-0.3V to (Vcc + 0.5V) affect reliability. Storage Temperature.......................-65C to +150C Power Dissipation V .......................................................................+7V CC 8-pin NSOIC...................................................500mW Input Voltages Logic.........................-0.3V to (Vcc + 0.5V) Drivers......................-0.3V to (Vcc + 0.5V) Receivers.........................................+/-5V ELECTRICAL CHARACTERISTICS T to T and V = 5V +/-5% unless otherwise noted. MIN MAX CC PARAMETERS MIN. TYP. MAX. UNITS CONDITIONS SP483/SP485 DRIVER DC Characteristics Differential Output Voltage Vcc Volts Unloaded R = see figure 1 Differential Output Voltage 2 Vcc Volts With Load R = 50 (RS-422) see figure Differential Output Voltage .5 Vcc Volts With Load R = 27 (RS-485) see figure Change in Magnitude of Driver 0.2 Volts R = 27 or R = 50 see figure 1 Differential Output Voltage for Complimentary states Driver Common Mode Output 3 Volts R = 27 or R = 50 see figure 1 Voltage Input High Voltage 2.0 Volts Applies to DE, DI, RE Input Low Voltage 0.8 Volts Applies to DE, DI, RE Input Current +/- 0 A Applies to DE, DI, RE Driver Short Circuit Current, 250 mA -7V V +12V O V = HIGH OUT Driver Short Circuit Current, 250 mA -7V V +12V O V = LOW OUT SP485 DRIVER AC Characteristics Maximum Data Rate 5 Mbps RE = 5V, DE = 5V Driver Input to Output, t 30 60 ns Figures 3 and 5, R = 54, PLH DIFF C = C = 00pF L L2 Driver Input to Output, t 30 60 ns Figures 3 and 5, R = 54, PHL DIFF C = C = 00pF L L2 Driver Skew 5 0 ns Figures 3 and 5, t = t - t SKEW DPHL DPLH Driver Rise or Fall Time 5 40 ns From 0%-90% R = 54 DIFF C = C = 100pF see figures 3 L L2 and 5 Exar Corporation 48720 Kato Road, Fremont CA, 94538 5 0-668-707 www .exar.com SP483 485 0 0627 2