SP3481/SP3485 +3.3V Low Power Half-Duplex RS-485 Transceivers with 10Mbps Data Rate RS-485 and RS-422 Transceivers Operates from a single +3.3V supply Interoperable with +5.0V logic Driver/Receiver Enable Low Power Shutdown Mode (SP3481) -7V to +12V Common-Mode Input Voltage Range Allows up to 32 transceivers on the serial bus Compatibility with the industry standard 75176 pinout Driver Output Short-Circuit Protection Now Available in Lead Free Packaging DESCRIPTION The SP3481 and the SP3485 are a family of +3.3V low power half-duplex transceivers that meet the specifications of the RS-485 and RS-422 serial protocols. These devices are pin-to- pin compatible with the Sipex SP481, SP483, and SP485 devices as well as popular industry standards. The SP3481 and the SP3485 feature Sipex s BiCMOS process, allowing low power operation without sacrificing performance. The SP3481 and SP3485 meet the electrical specifications of RS-485 and RS-422 serial protocols up to 10Mbps under load. The SP3481 is equipped with a low power Shutdown mode. RO 1 R 8 Vcc RE RE 2 7 B DE 3 6 A DI 4 5 GND D SP3481 and SP3485 10/15/02 SP3481/3485 Low Power Half-Duplex RS485 Transceivers Copyright 2002 Sipex Corporation 1ABSOLUTE MAXIMUM RATINGS These are stress ratings only and functional operation of the device at these ratings or any other above those indicated in the operation sections of the specifications below is not implied. Exposure to absolute maximum rating conditions for extended periods of time may affect reliability. V ............................................................................................. +6.0V CC Input Voltages Logic ..................................................... -0.3V to +6.0V Drivers ................................................... -0.3V to +6.0V Receivers ............................................................ 15V Output Voltages Drivers .................................................................. 15V Receivers .............................................. -0.3V to +6.0V Storage Temperature ...............................................-65C to +150C Power Dissipation per Package o o 8-pin NSOIC (derate 6.90mW/ C above +70 C) ..................... 600mW o o 8-pin PDIP (derate 11.8mW/ C above +70 C) ...................... 1000mW SPECIFICATIONS T = T to T and V = +3.3V 5% unless otherwise noted. AMB MIN MAX CC PARAMETERS MIN. TYP. MAX. UNITS CONDITIONS SP3481/SP3485 DRIVER DC Characteristics Differential Output Voltage GND V Volts Unloaded R = Figure 1 CC Differential Output Voltage 2 V Volts with load R = 50 (RS-422) Figure 1 CC Differential Output Voltage 1.5 V Volts with load R = 27 (RS-485) Figure 1 CC Change in Magnitude of Driver Differential Output Voltage for Complimentary States 0.2 Volts R = 27 or R = 50 Figure 1 Driver Common-Mode Output Voltage 3 Volts R = 27 or R = 50 Figure 1 Input High Voltage 2.0 Volts Applies to DE, DI, RE Input Low Voltage 0.8 Volts Applies to DE, DI, RE Input Current 10 A Applies to DE, DI, RE Driver Short-Circuit Current V = HIGH 250 mA -7V V +12V OUT O V = LOW 250 mA -7V V +12V OUT O SP3481/SP3485 DRIVER AC Characteristics Maximum Data Rate 10 Mbps RE = V , DE = V CC CC Driver Input to Output, t 20 40 60 ns Figures 2 and 8 PLH Driver Input to Output, t 20 40 60 ns Figures 2 and 8 PHL Differential Driver Skew 2 10 ns t - t Figures 2 and 9 DO1 DO2 Driver Rise or Fall Time 5 20 ns From 10% to 90% Figures 3 and 9 Driver Enable to Output High 52 120 ns Figures 4 and 10 Driver Enable to Output Low 60 120 ns Figures 5 and 10 Driver Disable Time from Low 40 120 ns Figures 5 and 10 Driver Disable Time from High 60 120 ns Figures 4 and 10 SP3481/SP3485 RECEIVER DC Characteristics Differential Input Threshold -0.2 +0.2 Volts -7V V +12V CM Input Hysteresis 20 mV V = 0V CM Output Voltage High V -0.4 Volts V = +200mV, -1.5mA CC ID Output Voltage Low 0.4 Volts V = -200mV, 2.5mA ID Three-State (High Impedance) Output Current +1 A 0V V V RE = V O CC CC Input Resistance 12 15 k -7V V +12V CM Input Current (A, B) V = 12V 1.0 mA DE = 0V, V = 0V or 3.6V, V = 12V IN CC IN Input Current (A, B) V = -7V -0.8 mA DE = 0V, V = 0V or 3.6V, V = -7V IN CC IN Short-Circuit Current 7 60 mA 0V V V CM CC 10/15/02 SP3481/3485 Low Power Half-Duplex RS485 Transceivers Copyright 2000 Sipex Corporation 2