SP331 EXAR | Alldatasheet

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Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 50-668-707 • www.exar.com SP33_00_0260 The SP33 is a programmable RS-232 and/or RS-485 transceiver IC. The SP33 contains four drivers and four receivers when selected in RS-232 mode; and two drivers and two receivers when selected in RS-485 mode. The SP33 also contains a dual mode which has two RS-232 drivers/receivers plus one differential RS-485 driver/receiver. The RS-232 transceivers can typically operate at 230kbps while adhering to the RS-232 speci- fications. The RS-485 transceivers can operate up to 10Mbps while adhering to the RS-485 specifications. The SP331 includes a self-test loopback mode where the driver outputs are internally configured to the receiver inputs. This allows for easy diagnostic serial port testing without using an external loopback plug. The RS-232 and RS-485 drivers can be disabled (High-Z output) by controlling a set of four select pins.

DESCRIPTION

  • +5V Only Operation
  • Software Programmable RS-232 or RS-485 Selection
  • Four RS-232 Transceivers in RS-232 Mode
  • Two RS-485 Full-Duplex Transceivers in RS-485 Mode
  • Two RS-232 Transceivers and One RS-485 Transceiver in Dual Mode
  • Self-Testing Loopback Mode
  • Full Driver Tri-State (Hi-Z) Control
  • Ideal for RS-232 to RS-485 conversion SP33 Programmable Dual RS-232/RS-485 Transceiver TI4 SEL_B TX4 TX3 VCC TX1 TX2 GND C1+ V+ (VDD) C2+ C1– C2– V– (VSS) TI3 TI2 TI1 SEL_C SEL_A SEL_D RX4 RX3 RX2 RX1 RI4 RI3 RI2 RI1 SP331 TYPICAL APPLICATIONS CIRCUIT SEL A TTL/CMOS TTL/CMOS TTL/CMOS 0.1µF C1+ C1- C2+ C2- SEL B 2 +5V VCC GND8 TTL/CMOS TTL/CMOS TTL/CMOS TTL/CMOS RS-485 RS-485 RS-485 0VSEL C RS-485 RS-485 RS-485 RI1 RI2 TX3 TX4 TX1 TX2 TI1 TI2 TI3 TI4 RX1 RX2 TTL/CMOS 21 R3 18RI4 RI3 RX3 RX4 15KΩ 400KΩ Vcc 400KΩ Vcc SEL D RS-485 RS-485 +5V +5V SP331 15KΩ 15KΩ 15KΩ 0.1µF 0.1µF 0.1µF

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 50-668-707 • www.exar.com SP33_00_0260 SPECIFICATIONS PARAMETER MIN. TYP. MAX. UNITS CONDITIONS LOgIC INPUTS VIL 0.8 Volts VIH 2.0 Volts LOgIC OUTPUTS VOL 0.4 Volts IOUT = -3.2mA VOH 2.4 Volts IOUT = .0mA RS-232 DRIVER DC Characteristics HIGH Level Output +5.0 +5.0 Volts RL = 3kΩ, VIN = 0.8V LOW Level Output -5.0 -5.0 Volts RL = 3kΩ, VIN = 2.0V Open Circuit Voltage -5 +5 Volts Short Circuit Current +/-00 mA VOUT = 0V Power Off Impedance 300 Ω VCC = 0V, VOUT = +/-2.0V AC Characteristics Slew Rate 30 V/µs RL = 3kΩ, CL = 50pF; VCC = +5.0V, TA @ 25°C Transistion Time .5 µs RL = 3kΩ, CL = 2500pF; between +/-3V, TA @ +25°C Maximum Data Rate 20 235 kbps RL = 3kΩ, CL = 2500pF Propagation Delay tPHL 2 8 µs Measured from 1.5V of VIN to 50% of VOUT; RL = 3kΩ Propagation Delay tPLH 2 8 µs RS-232 RECEIVER DC Characteristics HIGH Threshold .7 3.0 Volts LOW Threshold 0.8 .2 Volts Receiver Open Circuit Bias +2.0 Volts Input Impedance 3 5 7 kΩ VIN = +5V to -5V ABSOLUTE 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. Input Voltages Power Dissipation Package Derating: 28-pin WSOIC Limits are specified at TA = 25°C and VCC = +5.0V unless otherwise noted.

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 50-668-707 • www.exar.com SP33_00_0260 SPECIFICATIONS PARAMETER MIN. TYP. MAX. UNITS CONDITIONS RS-232 RECEIVER (continued) AC Characteristics Maximum Data Rate 20 235 kbps Propagation Delay tPHL 0.25 µs Measured from 50% of VIN to .5V of VOUT Propagation Delay tPLH 0.25 µs RS-485 DRIVER DC Characteristics Open Circuit Voltage 6.0 Volts Differential Output .5 5.0 Volts RL = 54Ω, CL = 50pF Balance +/-0.2 Volts |VT| - |VT| Common-Mode Output 3.0 Volts Output Current 28.0 mA RL = 54Ω Short Circuit Current +/-250 mA Terminated in -7V to +0V AC Characteristics Maximum Data Rate 0 Mbps RL = 54Ω Maximum Data Rate 8 Mbps TA = +85°C, Note Output Transition Time 30 50 ns Rise/Fall time, 0%-90% Propagation Delay tPHL 80 20 ns See Figures 2 & 4, RDIFF = 54Ω, CL = CL2 = 00pFPropagation Delay tPLH 80 20 ns Driver Output Skew 0 20 ns Per Figure 4, tSKEW = |tPHL - tPLH| RS-485 RECEIVER DC Characteristics Common Mode Range -7.0 +2 Volts Receiver Sensitivity +/-0.2 +/-0.3 Volts -7V ≤ VCM ≤ +12V Input Impedance 2 5 kΩ -7V ≤ VCM ≤ +12V AC Characteristics Maximum Data Rate 0 Mbps Maximum Data Rate 8 Mbps TA = +85°C, Note Propagation Delay tPHL 30 200 ns See Figures 2 & 6, RDIFF = 54Ω, CL = CL2 = 00pFPropagation Delay tPLH 30 200 ns Differential Receiver Skew 0 20 ns tSKEW = |tPHL - tPLH|, RDIFF = 54Ω, CL = CL2 = 00pF ENABLE TIMINg RS-485 DRIVER Enable Time (see Figures 3 and 5) Enable to LOW 90 50 ns CL = 5pF, S Closed Enable to HIGH 90 50 ns CL = 5pF, S2 Closed Disable Time (see Figures 3 and 5) Disable from LOW 80 20 ns CL = 5pF, S Closed Disable from HIGH 80 20 ns CL = 5pF, S2 Closed Limits are specified at TA = 25°C and VCC = +5.0V unless otherwise noted.

1 Unit Load

Figure 2. Driver/Receiver Timing Test Circuit Figure 3. Driver Timing Test Load #2 Circuit Limits are specified at TA = 25°C and VCC = +5.0V unless otherwise noted.

Figure 0. Typical Operating Circuit

0 RS-232/RS-485 RS-232 (2ch) / RS-485 (ch) Loopback

0 RS-485/RS-232 RS-485 (ch) / RS-232 (2ch) Loopback

0 RS-485 T tri-state RS-485; T3 active RS-485

0 RS-485 T active RS-485; T3 tri-state RS-485

Table 1. Mode Function Table. (Refer to Control Logic Confirmations for Block Diagrams) blocks is described in more detail below. compared to older less efficient designs. tors C and C2 are initially charged to +5V. negative side is connected to ground.

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 50-668-707 • www.exar.com SP33_00_0260 Drivers The SP331 has four independent RS-232 single-ended drivers and two differential RS-485 drivers. Control for the mode selec- tion is done via a four–bit control word. The drivers are pre-arranged such that for each mode of operation the relative position and functionality of the drivers are set up to ac- commodate the selected interface mode. As the mode of the drivers is changed, the elec- trical characteristics will change to support the requirements of clock, data, and control line signal levels. Unused driver inputs can be left floating; however, to ensure a desired state with no input signal, pull–up resistors to +5V or pull–down resistors to ground are suggested. Since the driver inputs are both TTL or CMOS compatible, any value resistor less than 100kΩ will suffice. When in RS-232 mode, the single-ended RS-232 drivers produce compliant RS-232E and ITU V.28 signals. Each of the four driv- ers output single-ended bipolar signals in access of ±5V with a full load of 3kΩ and 2500pF applied as specified. These drivers can also operate at least 20kbps. When programmed to RS-485 mode, the differential RS-485 drivers produce complaint RS-485 signals. Each RS-485 driver outputs a unipolar signal on each output pin with a magnitude of at least .5V while loaded with a worst case of 54Ω between the driver's two output pins. The signal levels and drive capability of the RS-485 drivers allow the drivers to also comply with RS-422 levels. The transmission rate for the differential drivers is 10Mbps. Receivers The SP331 has four single-ended receivers when programmed for RS-232 mode and two differential receivers when programmed for RS-485 mode. Control for the mode selection is done via a 4–bit control word, as in the drivers. As the operating mode of the receivers is changed, the electrical characteristics will change to support the requirements of the appropriate serial standard. Unused receiver inputs can be left floating without causing oscillation. To ensure a desired state of the receiver output, a pull–up resistor of 100kΩ to +5V should be connected to the inverting input for a logic low, or the non–inverting input for a logic high. For single-ended receiv - ers, a pull–down resistor to ground of 5kΩ is internally connected, which will ensure a logic high output. The RS-232 receiver has a single–ended input with a threshold of 0.8V to 2.4V. The RS-232 receiver has an operating voltage range of ±5V and can receive signals up to 20kbps. RS-232 receivers are used in RS-232 mode for all signal types include data, clock, and control lines of the RS-232 serial port. The differential RS-485 receiver has an input impedance of 15kΩ and a differential thresh- old of ±200mV. Since the characteristics of an RS-422 receiver are actually subsets of RS-485, the receivers for RS-422 require - ments are identical to the RS-485 receivers. All of the differential receivers can receive data up to 10Mbps. Select Mode Pins Similar to our SP500 family of multiprotocol products, the SP331 has the ability to change the configuration of the drivers and receiv - ers via a 4–bit switch. Referring to Table ; RS-232 mode, RS-485 mode, or two differ- ent combinations of RS-232/RS-485 can be configured using the SEL_A and SEL_B pins. The drivers can be put into tri-state mode by using the SEL_C and SEL_D pins. All receivers remain active during any tri-state condition of the drivers. Loopback Mode Loopback is invoked by asserting "xx11" into the select pins. In RS-232/RS-485 or RS-485/RS-232 loopback mode, the RS-232 driver outputs loop back into the RS-232 receiver inputs and the RS-485 differential driver loops back into the RS-485 receiver. During loopback, the driver outputs and receiver inputs are disconnected from the outside world. The driver outputs are in tri- state and the receiver inputs are disabled. The input impedance of the receivers during loopback is approximately 15kΩ to ground.

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 50-668-707 • www.exar.com SP33_00_0260 SEL A 0 0 0 0 0 0 SEL B 0 0 0 0 0 0 SEL C 0 0 0 0 0 0 0 0 SEL D 0 0 0 0 0 0 0 0 SP331 CONTROL LOgIC CONFIgURATION (Refer to Table 1) SP331 LOOPBACK (Refer to Table 1) T3 3 TX4 TX3 TX1 TX2 TI3 R1 16 15RI1 RI2 RX1 T126 TI1 R3 18 17RI3 RI4 RX3 TX4 TX3 TX1 TX2 TI3 R1 16 15RI1 RI2 RX1 RX321

26 TI1

28 TI3

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 50-668-707 • www.exar.com SP33_00_0260

Exar Corporation 48720 Kato Road, Fremont CA, 94538 • 50-668-707 • www.exar.com SP33_00_0260

ORDERINg INFORMATION

Model Temperature Range Package Types

REVISION HISTORy

0-04-05 - Legacy Sipex Datasheet Note 1 and change maximum RS-485 data rate at +85C. Update ABS Max Rating table. Notice EXAR Corporation reserves the right to make changes to any products contained in this publication in order to improve design, performance or reliabil- ity. EXAR Corporation assumes no representation that the circuits are free of patent infringement. Charts and schedules contained herein are only for illustration purposes and may vary depending upon a user's specific application. While the information in this publication has been carefully checked; no responsibility, however, is assumed for inaccuracies. EXAR Corporation does not recommend the use of any of its products in life support applications where the failure or malfunction of the product can reasonably be expected to cause failure of the life support system or to significantly affect its safety or effectiveness. Products are not authorized for use in such applications unless EXAR Corporation receives, in writting, assurances to its satisfaction that: (a) the risk of injury or damage has been minimized ; (b) the user assumes all such risks; (c) potential liability of EXAR Corporation is adequately protected under the circumstances. Copyright 200 EXAR Corporation Datasheet January 200 Send your Interface technical inquiry with technical details to: uarttechsupport@exar.com Reproduction, in part or whole, without the prior written consent of EXAR Corporation is prohibited. Note: /TR = Tape and Reel