SP335E

SP335E EXAR | Alldatasheet

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Exar Corporation 48720 Kato Road, Fremont CA, 94538 • (510) 668-7000 • FAX (510) 668-7017 • www.exar.com SP335E RS-232/RS-485/RS-422 TRANSCEIVER WITH INTERNAL TERMINATION Sept 2013 Rev. 1.0.0 GENERAL DESCRIPTION The SP335 is an advanced multiprotocol transceiver supporting RS-232, RS-485, and RS-422 serial standards. Integrated cable termination and multiple configuration modes allow all three protocols to be used interchangeably over a single cable or connector with no additional switching components. Full operation requires only four external charge pump capacitors. The RS-485/RS-232 mode pin selects RS-485 mode when high, and RS-232 mode when low. In RS-485 mode, the TERM pin enables the differential 120 : termination, and the HALF/ FULL p i n c o n f i g u r e s t h e transceiver as either half or full duplex. The high speed drivers operate up to 20Mbps in RS- 485/422 modes, and up to 1Mbps in RS-232 mode. All drivers can be slew limited to 250kbps in any mode to minimize electromagnetic interference (EMI) by setting the dedicated SLEW pin low. All transmitter outputs and receiver inputs feature robust electrostatic discharge (ESD) protection to ±15kV IEC 61000-4-2 Airg ap, ±15kV Human Body Model (HBM) and ±8kV IEC 61000-4-2 Contact. Each receiver output has full fail-safe protection to avoid system lockup, oscillation, or indeterminate states by defaulting to logic-high output level when the inputs are open, shorted, or terminated but undriven. No external biasing resistors are required. The RS-232 receiver inputs include a 5k : pull-down to ground when in RS-232 mode. The RS-485/422 receiver inputs are high impedance (>96k : w h e n termination is disabled), allowing up to 256 devices on a single communication bus (1/8th unit load). The SP335 operates from a single power supply, either 3.3V or 5V, with low idle current. The shutdown mode consumes less than 1 µA in low power standby operation with RS-232 receivers enabled.

FEATURES

x Pin-Selectable Cable Termination x No External Resistors Required for RS -485/422 Termination or Biasing x Robust ESD Protection: I ±15kV IEC 61000-4-2 Air Gap Discharge I ± 8kV IEC 61000-4-2 Contact Discharge I ±15kV Human Body Model (HBM) x 20Mbps RS-485 and 1Mbps RS-232 Data Rates x Pin-Selectable 250kbps Slew Limiting x Single Supply Operation from +3V to +5.5V x 1.65V to 5.5V Logic Interface VL pin x 2 Drivers, 2 Receivers RS-232/V.28 x 1 Driver, 1 Receiver RS-485/422 I Full or Half Duplex Configuration I 1/8th Unit Load, up to 256 receivers on bus x RS-485/422 Enhanced Receiver Fail-safe for open, shorted, or terminated but idle inputs x 10nA Shutdown Supply Current (typical) x Small 32 QFN package (5mm x 5mm) TYPICAL APPLICATIONS x Software Programmable Serial Ports (RS-232, RS-422, RS-485) x Industrial and Single Board Computers x Industrial and Process Control Equipment x Point-Of-Sale Equipment x HVAC Controls and Networking Equipment x Building Security and Automation

ORDERING INFORMATION

PART NUMBER PACKAGE OPERATING TEMPERATURE RANGE DEVICE STATUS SP335EER1-L 32-pin QFN -40°C to +85°C In Production SP335ECR1-L 32-pin QFN 0°C to +70°C In Production NOTE: Tape and Reel part numbers are SP335ExR1-L/TR, -L = Green / RoHS Compliant

RS-232/RS-485/RS-422 TRANSCEIVER WITH INTERNAL TERMINATION REV. 1.0.0 CAUTION: ESD (ElectroStatic Discharge) sensitive device. Permanent damage may occur on unconnected devices subject to high energy electrostatic fields. Unused devices must be stored in conductive foam or shunts. Personnel should be properly grounded prior to handling this device. The protective foam should be discharged to the destination socket before devices are removed. ESD PROTECTION 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 to the specifications below is not implied. Exposure to absolute maximum rating conditions for extended periods of time may affect reliability and cause permanent damage to the device. Supply Voltage VCC -0.3V to +6.0V Logic Interface Voltage VL VL d VCC Voltage at TTL Input Pins -0.3V to +6.0V Receiver Input Voltage (from Ground) ±18V Driver Output Voltage (from Ground) ±18V Short Circuit Duration, TX out to Ground Continuous Storage Temperature Range -65°C to +150°C Lead Temperature (soldering, 10s) +300°C Power Dissipation 32-pin 5x5 QFN (derate 26.0mW/°C above +70°C) 1400mW MIN. TYP. MAX. UNITS TX Output & RX Input Pins ±15 kV IEC 61000-4-2 Airgap ± 8 kV IEC 61000-4-2 Contact ±15 kV Human Body Model (HBM) All Other Pins ± 3 kV Human Body Model (HBM)

REV. 1.0.0 RS-232/RS-485/RS-422 TRANSCEIVER WITH INTERNAL TERMINATION

ELECTRICAL CHARACTERISTICS

UNLESS OTHERWISE NOTED: SYMBOL PARAMETERS MIN. TYP. MAX. UNITS CONDITIONS DC CHARACTERISTICS ICC Supply Current (RS-232) 1 2.5 mA No load, Idle inputs, RS-485/RS-232 = 0V ICC Supply Current (RS-485/422) 1.8 4.5 mA No load, Idle inputs, RS-485/RS-232 = VCC ICC Vcc Shutdown Current 0.01 1 µA SHDN = 0V, Receiver inputs open or grounded TRANSMITTER and LOGIC INPUTS (PINS 10 - 15, 20 - 22) VIL Logic Input Voltage Low VL 3 V VIH Logic Input Voltage High 2VL V IINL Logic Input Leakage Current ±0.01 ±1 µA IINPD Logic Input Pulldown Current 10 50 µA RE, TERM, & FD_TX_TERM VIN = VL VHYS Logic Input Hysteresis 200 mV RS-232 and RS-485/422 RECEIVER OUTPUTS (PINS 6 & 7) VOL Receiver Output Voltage Low 0.4 V IOUT = 1.5mA VOH Receiver Output Voltage High VL-0.6 V IOUT = -1.5mA IOSS Receiver Output Short Circuit Current ±20 ±85 mA 0 d VOd VL IOZ Receiver Output Leakage Current ±0.05 ±1 µA 0 dVOd VL, Receivers disabled

RS-232/RS-485/RS-422 TRANSCEIVER WITH INTERNAL TERMINATION REV. 1.0.0 ELECTRICAL CHARACTERISTICS (Continued) UNLESS OTHERWISE NOTED: SYMBOL PARAMETERS MIN. TYP. MAX. UNITS CONDITIONS RS-232 SINGLE-ENDED RECEIVER INPUTS (PINS 18 & 19) VIN Input Voltage Range -15 +15 V VIL Input Threshold Low 0.6 1.2 V VCC = 3.3V 0.8 1.5 V VCC = 5.0V VIH Input Threshold High 1.5 2.0 V VCC = 3.3V 1.8 2.4 V VCC = 5.0V VHYS Input Hysteresis 0.5 V RIN Input Resistance 3 5 7 k: -15V d VIN d +15V RS-232 SINGLE-ENDED TRANSMITTER OUTPUTS (PINS 3 & 4) VOUT Output Voltage Swing ±5.0 ±5.5 V Outputs loaded with 3k: to Gnd ROFF Output Power Off Impedance 300 10M : VCC = 0V, VOUT = ±2V ISC Output Short Circuit Current ±30 ±60 mA VOUT = 0V IO Output Leakage Current ±125 µA SHDN = 0V, VOUT = ±9V, VCC = 0V or 5.5V

REV. 1.0.0 RS-232/RS-485/RS-422 TRANSCEIVER WITH INTERNAL TERMINATION ELECTRICAL CHARACTERISTICS (Continued) UNLESS OTHERWISE NOTED: SYMBOL PARAMETERS MIN. TYP. MAX. UNITS CONDITIONS RS-485/422 DIFFERENTIAL RECEIVER INPUTS (A,B) RIN Receiver Input Resistance 96 k: Termination disabled, -7V d VCM d +12V IIN Receiver Input Current 125 µA VIN = +12V -100 µA VIN = -7V VTH Receiver Differential Threshold Voltage -200 -125 -50 mV -7V d VCM d +12V 'VTH Receiver Input Hysteresis 25 mV RTERM Termination Resistance 100 120 155 : Termination enabled, Figure 4 -7V d VCM d +12V RTERM Termination Resistance 100 120 140 : Termination enabled, Figure 4 VCM = 0V RS-485/422 DIFFERENTIAL DRIVER OUTPUTS (Y, Z) VOD Differential Driver Output

1.5 VCC V RL = 54: (RS-485), Figure 5

1.5 VCC V -7V d VCM d +12V, Figure 6

2 VCC V RL = 100: (RS-422), Figure 5

_'VOD_ Change In Magnitude of Differential Output Voltage 0.2 V RL = 54: or 100:, Figure 5 VCM Driver Common Mode Output Voltage 3 V RL = 54: or 100:, Figure 5 _'VCM_ Change In Magnitude of Common Mode Output Voltage 0.2 V RL = 54: or 100:, Figure 5 IOSD Driver Output Short Circuit Current ±250 mA -7V d VY or VZd +12V, Figure 7 IO Driver Output Leakage Current ±125 µA DE = 0V or SHDN = 0V, VY or VZ = -7V or +12V, VCC = 0V or 5.5V

RS-232/RS-485/RS-422 TRANSCEIVER WITH INTERNAL TERMINATION REV. 1.0.0 PIN DESCRIPTIONS Pin Name RS-232 RS-485 Full Duplex RS-485 Half Duplex

2 GND Ground

3 T1OUT, B/Z Transmitter 1 Output Z Driver Neg Output B/Z Neg Input/Output

4 T2OUT, A/Y Transmitter 2 Output Y Driver Pos Output A/Y Pos Input/Output

6 R1OUT Receiver 1 Output X X

7 R2OUT, RO Receiver 2 Output Receiver TTL Output Receiver TTL Output

10 SHDN Low power shutdown mode when low

11 SLEW Data rate limited to 250kbps when low

12 FD_TX_TERM X

120: Y-Z termination enabled when both TERM and FD_TX_TERM are high X

13 TERM X 120: A-B termination enabled when high

14 RS-485/RS-232 0 1 1

15 HALF/FULL X 0 1

17 GND Ground

18 R2IN, A Receiver 2 Input A Pos Receiver Input X

19 R1IN, B Receiver 1 Input B Neg Receiver Input X

20 RE X Receiver enabled when low

21 T2IN, DE Transmitter 2 Input Driver enabled when high

22 T1IN, DI Transmitter 1 Input Driver TTL Input

25 V- Charge pump negative supply, 0.1µF from ground

26 C2- Charge pump cap 2 negative lead

27 C2+ Charge pump cap 2 positive lead, 0.1µF 28 V+ Charge pump positive supply, 0.1µF to ground 29 C1+ Charge pump cap 1 positive lead, 0.1µF 30 VL Logic Supply for TTL Inputs and Outputs, VL = +1.65V to +5.5V or tie to VCC 31 VCC Main Supply, VCC = +3.0V to +5.5V, bypass to ground with 1.0µF

32 C1- Charge pump cap 1 negative lead

REV. 1.0.0 RS-232/RS-485/RS-422 TRANSCEIVER WITH INTERNAL TERMINATION SUGGESTED DB9 CONNECTOR PINOUT DB9 Pin RS-232 RS-485 Full Duplex RS-485 Half Duplex

2 RXD RX+

3 TXD TX- Data-

5 Ground

7 RTS TX+ Data+

8 CTS RX-

FIGURE 1. RS-232 MODE Pins 12, 13, and 20 have 300k: internal pull-downs (not shown).

FIGURE 2. RS-485 FULL DUPLEX MODE Pins 12, 13, and 20 have 300k: internal pull-downs (not shown). Termination control follows the truth table on page 20. The full duplex driver termination is enabled only when both TERM and FD_TX_TERM are high.

FIGURE 3. RS-485 HALF DUPLEX MODE Pins 12, 13, and 20 have 300k: internal pull-downs (not shown). Termination control follows the truth table on page 20.

FIGURE 12. RS-485/422 RECEIVER OUTPUT ENABLE/DISABLE TIMES

FIGURE 13. RS-485/422 DRIVER OUTPUT ENABLE/DISABLE TIMES

RS-232/RS-485/RS-422 TRANSCEIVER WITH INTERNAL TERMINATION REV. 1.0.0 PRODUCT SUMMARY The SP335 is an advanced multiprotocol transceiver supporting RS-232, RS-485, and RS-422 serial standards. Integrated cable termination and multiple configuration modes allow all three protocols to be used interchangeably over a single cable or connector with no additional switching components. Full operation requires only four external charge pump capacitors. INTERNALLY SWITCHED CABLE TERMINATION Enabling and disabling the RS-485/422 termination resistor is one of the largest challenges system designers face when sharing a single connector or pair of lines across multiple serial protocols. A termination resistor may be necessary for accurate RS-485/422 communication, but must be removed when the lines are used for RS-232. SP335 provides an elegant solution to this problem by integrating the termination resistor and switching control, and allowing it to be switched in and out of the circuit with a single pin. No external switching components are required. Termination on the receiver inputs will be enabled if both TERM and RS-485/RS-232 are high. ENHANCED FAILSAFE The enhanced failsafe feature of the SP335 guarantees a logic-high receiver output when the receiver inputs are open, shorted, or terminated but idle/undriven. The enhanced failsafe interprets 0V differential as a logic high with a minimum 50mV noise margin, while maintaining compliance with the EIA/TIA-485 standard of ±200mV. No external biasing resistors are required, further easing the usage of multiple protocols over a single connector. ±15kV ESD PROTECTION ESD protection structures are incorporated on all pins to protect against electrostatic discharges encountered during handling and assembly. The bus pins (driver outputs and receiver inputs) have extra protection structures, which have been tested up to ±15kV without damage. These structures withstand high ESD in all states: normal operation, in shutdown, and when powered off. ESD protection is be tested in various ways. Exar uses the following methods to qualify the protection structures designed into SP335: ±8kV using IEC 61000-4-2 Contact Discharge ±15kV using IEC 61000-4-2 Airgap Discharge ±15kV using the Human Body Model (HBM) The IEC 61000-4-2 standard is more rigorous than HB M, resulting in lower voltage levels compared with HBM for the same level of ESD protection. Because IEC 61000-4-2 specifies a lower series resistance, the peak current is higher than HBM. The SP335 has passed both HBM and IEC 61000-4-2 testing without damage. VARIABLE LOGIC LEVEL VOLTAGE The SP335 includes a VL pin, which reduces the logic level thresholds to interface with processors operating at reduced supply voltages. This pin should be connected to the supply voltage of the processor, or can be connected to VCC for typical logic levels.

REV. 1.0.0 RS-232/RS-485/RS-422 TRANSCEIVER WITH INTERNAL TERMINATION TRUTH TABLES TABLE 1: RS-232 TX TRUTH TABLE INPUTS OUTPUTS SHDN RS-485/RS-232 DI/T1IN, DE/T2IN Z(B)/T1OUT, Y(A)/T2OUT

0 X X 1/8th unit load

TABLE 2: RS-232 RX TRUTH TABLE INPUTS OUTPUTS SHDN RS-485/RS-232 B/R1IN, A/R2IN R1OUT, RO/R2OUT X 0 0 1 X 0 1 0 X 0 Inputs open 1 X 1 X R1OUT High-Z, RO/R2OUT in RS-485 Mode

RS-232/RS-485/RS-422 TRANSCEIVER WITH INTERNAL TERMINATION REV. 1.0.0 The DE and RE pins have no effect on the termination setting in any mode. TABLE 3: RS-485/422 TX TRUTH TABLE INPUTS OUTPUTS SHDN RS-485/RS-232 DE/T2IN DI/T1IN Z(B)/T1OUT Y(A)/T2OUT

0 X X X 1/8th unit load 1/8th unit load

1 1 0 X 1/8th unit load 1/8th unit load 1 1 1 0 1 0 1 1 1 1 0 1 X 0 X X RS-232 Mode TABLE 4: RS-485/422 RX TRUTH TABLE INPUTS OUTPUT RS-485/RS-232 SHDN HALF/FULL RE (A-B) (Y-Z) RO/R2OUT 1 0 X X X X High-Z 1 1 0 0 t-50mV X 1 1 1 0 0 d -200mV X 0 1 1 0 0 Floating X 1 1 1 1 0 X t-50mV 1 1 1 1 0 X d -200mV 0 1 1 1 0 X Floating 1 1 1 X 1 X X High-Z

0 X X X X X RS-232 Mode

TABLE 5: RS-485/422 TERMINATION TRUTH TABLE FD_TX_TERM TERM RS-485/RS-232 HALF/FULL TX TERM RX TERM PIN 12 PIN 13 PIN 14 PIN 15 PINS 3-4 PINS 18-19 X 0 1 0 - - 0 1 1 0 - ON 1 1 1 0 ON ON X 0 1 1 - - X 1 1 1 ON - X X 0 X - -

FIGURE 14. QFN 32

EXAR Corporation reserves the right to make changes to the products contained in this publication in order to improve design, performance or reliability. EXAR Corporation assumes no responsibility for the use of any circuits described herein, conveys no license under any patent or other right, and makes no representation that the circuits are free of patent infringement. Charts and schedules contained here in 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 writing, assurances to its satisfaction that: (a) the risk of injury or damage has been minimized; (b) the user assumes all such risks; (c) potential liabilit y of EXAR Corporation is adequately protected under the circumstances. Copyright 2013 EXAR Corporation Datasheet Sept 2013. For technical support please email Exar’s Serial Technical Support group at: serialtechsupport@exar.com. Reproduction, in part or whole, without the prior written consent of EXAR Corporation is prohibited. SP335E RS-232/RS-485/RS-422 TRANSCEIVER WITH INTERNAL TERMINATION REV. 1.0.0

REVISION HISTORY

Sept 2013 1.0.0 Production Release