® SP332 RS-232/RS-485 Multi-Mode Serial Transceiver ■ ■ ■ ■ ■ +5V-Only Single Supply Operation 4 Drivers, 4 Receivers RS-232 2 Drivers, 2 Receivers RS-485 Loop Back Function for Self Test 28 Pin SOIC Packaging DESCRIPTION… The SP332 is a monolithic device that contains both RS-232 and RS-485 line drivers and receivers. The configuration of the SP332 can be changed at any time by changing the logic state of two control input pins. The device also includes a loop back function which internally connects driver outputs to receiver inputs for a chip self test. A Sipex-patented charge pump (5,306,954) allows +5V-only operation. RS-232 Mode 9 0.1µF 0.1µF 0V 0V Full Duplex RS-485 +5V C1+ 12 C111 C2+ 13 C224 SEL A 2 SEL B +5V 5 VCC 5 V+ SP332 V- 9 0.1µF 10 0.1µF 14 0.1µF LOOP 23 BACK Vcc 0.1µF TTL/CMOS RS-232 +5V TTL/CMOS +5V TTL/CMOS RS-232 TTL/CMOS RS-232 TTL/CMOS 400KΩ TTL/CMOS 26 TI1 Vcc TX1 6 T1 400KΩ TTL/CMOS 27 TI2 Vcc TX2 7 T2 400KΩ TTL/CMOS 28 TI3 TX3 4 T3 Vcc TTL/CMOS 400KΩ TTL/CMOS 1 TI4 TX4 3 T4 RS-232 TTL/CMOS TTL/CMOS 19 RX1 RI1 15 R1 TTL/CMOS RS-232 5KΩ TTL/CMOS 20 RX2 RI2 16 R2 TTL/CMOS 21 RX3 RI3 17 R3 VCC C1+ C1- 11 C2+ 13 C224 SEL A 2 SEL B 26 TI1 27 TI2 22 RX4 RI4 18 R4 TTL/CMOS TTL/CMOS RS-232 5KΩ 8 TGoddard/SP332/9617R0 GND SHUT DOWN TX2 7 Vcc TX4 3 T3 TI4 22 RS-485/RS-232 TX3 4 RI2 16 R1 RI1 15 RS-485/RS-232 RS-485/RS-232 RS-485/RS-232 RS-485/RS-232 RS-485/RS-232 R3 RI3 17 RS-485/RS-232 RS-485/RS-232 RX4 GND TTL/CMOS SP332 RS-232/RS-485 Multi-Mode Serial Transceiver 1 TTL/CMOS RX2 21 RX3 8 25 0.1µF 23 RI4 18 RS-232 0.1µF 14 TX1 6 19 RX1 20 V- 10 T1 28 TI3 1 V+ LOOP BACK Vcc 5KΩ TTL/CMOS SP332 RS-232 5KΩ TTL/CMOS 12 SHUT DOWN 25 TTL/CMOS © Copyright 2000 Sipex Corporation 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. VCC............................................................................................................+12V Input Voltages Logic........................................................-0.5V to (VCC+0.5V) Drivers..................................................-0.5V to (VCC+0.5V) Receivers.................................................±30V@≤100mA Driver Outputs......................................................................................±15V Storage Temperature..................................................-65˚C to +150˚C Power Dissipation..........................................................................1000mW SPECIFICATIONS TMIN to TMAX and VCC = 5V±5% unless otherwise noted. PARAMETER RS-485 DRIVER DC Characteristics Differential Output Voltage Differential Output Voltage GND 2.0 Differential Output Voltage 1.5 Change in Magnitude of Driver Differential Output Voltage for Complementary States Driver Common-Mode Output Voltage Input High Voltage MIN. TYP. UNITS CONDITIONS VCC 5.0 Volts Volts 5.0 Volts Unloaded; R=∞; see figure 1 With Load; R=50Ω (RS-422); see figure 1 With Load; R=27Ω (RS-485); see figure 1 0.2 Volts R=27Ω or R=50Ω; see figure 1 3 Volts Volts 0.8 Volts ±10 µA µA µA R=27Ω or R=50Ω; see figure 1 Applies to transmitter inputs, SEL A, SEL B, SD, LB Applies to SEL A, SEL B, SD, LB Applies to: transmitter inputs, LB SEL A, SEL B, SD, 250 250 mA mA -7V≤VO≤10V -7V≤VO≤10V 70 180 Mbps ns 70 180 ns 5 10 ns 15 40 ns 2.0 Input Low Voltage Input Current Pull-Up Current Pull-Down Current Driver Short-Circuit Current VOUT= HIGH VOUT= LOW AC Characteristics Driver Data Rate Driver Input to Output tPLH Driver Input to Output tPHL Driver Skew Driver Rise or Fall Time RS-485 RECEIVER DC Characteristics Differential Input Threshold Input Hysteresis Output Voltage High Output Voltage Low Input Resistance Input Current (A, B); VIN= 12V Input Current (A, B); VIN= -7V Short Circuit Current TGoddard/SP332/9617R0 MAX. 1.5 3.0 35 35 10 3 -0.2 +0.2 +1.5 Volts mV Volts Volts kΩ mA -0.8 85 mA mA 70 3.5 0.4 12 15 RDIFF=54Ω, CL1=CL2=100pF; see figures 3 and 6 RDIFF=54Ω, CL1=CL2=100pF; see figures 3 and 6 From output to output; see figures 3 and 6 From 10% to 90%; RDIFF=54Ω, CL1=CL2=100pF; see figures 3 and 6 -7V≤VCM≤12V VCM=0V IO=-4mA, VID=+200mV IO=+4mA, VID=-200mV -7V≤VCM≤12V VIN= 12V, A is the non-inverting receiver input. B is the inverting receiver input VIN= -7V 0V≤VCM≤VCC SP332 RS-232/RS-485 Multi-Mode Serial Transceiver 2 © Copyright 2000 Sipex Corporation SPECIFICATIONS (CONTINUED) TMIN to TMAX and VCC = 5V±5% unless otherwise noted. PARAMETER AC Characteristics Receiver Data Rate Receiver Input to Output tPLH Receiver Input to Output tPHL Diff. Receiver Skew |tPLH-tPHL| MIN. TYP. MAX. UNITS 130 250 Mbps ns 130 250 ns 10 13 RS-232 DRIVER DC Characteristics TTL Input Levels VIL VIH Voltage Outputs High Level Output Low Level Output Open Circuit Output Short Circuit Current Power Off Impedance AC Characteristics Transmission Rate Transition Time 0.8 2.0 120 1.56 Slew Rate AC Characteristics Transmission Rate Transition Time Propagation Delay tPHL tPLH +15.0 -5.0 ±15 ±100 300 tPLH Volts Volts +5.0 -15.0 Propagation Delay tPHL RS-232 RECEIVER TTL Output Levels VOL VOH Receiver Input High Threshold Low Threshold Input Voltage Range Input Impedance Hysteresis ns Volts Volts Volts mA Ohms kbps µs RDIFF=54Ω, CL1=CL2=100pF; Figures 3 and 8 RDIFF=54Ω, CL1=CL2=100pF; Figures 3 and 7 RDIFF=54Ω, CL1=CL2=100pF; Figures 3 and 7 Applies to transmitter inputs, SEL A, SEL B, SD, LB Applies to transmitter inputs, SEL A, SEL B, SD, LB RL=3kΩ to Gnd RL=3kΩ to Gnd RL=∞ VOUT = 0V VCC=0V; VOUT= ±2V Rise/fall time, +3V to -3V; -3V to +3V RL=3kΩ, CL=2500pF 2 4 µs 3 6 µs 10 30 V/µs 0.4 Volts 3.0 Volts Volts Volts kOhms Volts VIN=±15V VCC=+5V kbps ns Rise/fall time 10% to 90% 3.5 0.8 -15 3 0.2 CONDITIONS 2.1 1.6 5 0.5 +15 7 1.0 120 50 RL=3kΩ, CL=2500pF; From 1.5V of TIN to 50% of VOUT RL=3kΩ, CL=2500pF; From 1.5V of TIN to 50% of VOUT RL=3kΩ, CL=50pF; From +3V to -3V or -3V to +3V ISINK = 4mA ISOURCE = -4mA 100 100 300 200 ns ns From 50% of VIN to 1.5V of ROUT From 50% of VIN to 1.5V of ROUT POWER REQUIREMENTS No Load Supply Current Full Load Supply Current 19 90 25 120 mA mA Shutdown Supply Current 5 50 µA No load; VCC=5.0V; TA=25˚C RS-232 drivers R L=3kΩ to Gnd; DC Input RS-485 drivers RL=54Ω from A to B; DC Input TA=25˚C, VCC=5.0V TGoddard/SP332/9617R0 SP332 RS-232/RS-485 Multi-Mode Serial Transceiver 3 © Copyright 2000 Sipex Corporation A VOD R Test Point Receiver Output R CRL VOC 1K 1K B S2 Figure 1. RS-485 Driver DC Test Load Circuit A DI VCC S1 CL1 RDIFF A Figure 2. Receiver Timing Test Load Circuit RO Output Under C L Test B B CL2 15pF Figure 4. RS-485 Driver Timing Test Load #2 Circuit f = 1MHz; tR ≤ 10ns; tF ≤ 10ns +3V 1.5V 1.5V DI 0V tPLH B DIFFERENTIAL OUTPUT VCC S1 S2 Figure 3. RS-485 Driver/Receiver Timing Test Circuit DRIVER OUTPUT 500 VO tPHL tPLH 1/2VO 1/2VO A tSKEW tSKEW VO+ 0V VA – VB VO– tR tF Figure 6. RS-485 Driver Propagation Delays f = 1MHz; tR ≤ 10ns; tF ≤ 10ns VOD2+ A–B VOD2– 0V VOH 1.5V R VOL INPUT 0V 1.5V OUTPUT tPHL tPHL Figure 7. RS-485 Receiver Propagation Delays TGoddard/SP332/9617R0 SP332 RS-232/RS-485 Multi-Mode Serial Transceiver 4 © Copyright 2000 Sipex Corporation RS-232 (V.28) Receivers... The RS-232 receivers convert RS-232 input signals to inverted TTL signals. Each of the four receivers features 500mV of hysteresis margin to minimize the affects of noisy tranmission lines. The inputs also have a 5kΩ resistor to ground, in an open circuit situation the input of the receiver will be forced low, committing the output to a logic high state. The input resistance will maintain 3kΩ-7kΩ over a ±15V range. The maximum operating voltage range for the receiver is ±30V, under these conditions the input current to the receiver must be limited to less than 100mA. Due to the on-chip ESD protection circuitry, the receiver inputs will be clamped to ±15V levels. The RS-232 receivers can operate up to 120kbps. THEORY OF OPERATION... The SP332 is a single chip device that can be configured via software for either RS-232, RS485 or both interface modes at any time. The SP332 is made up of three basic circuit elements, single-ended drivers and receivers, differential drivers and receivers and charge pump. DIFFERENTIAL DRIVER/RECEIVER... RS-485, RS-422 Drivers... The differential drivers and receivers comply with the RS-485 and RS-422 standards. The driver circuits are able to drive a minimum of 1.5V when terminated with a 54Ω resistor across the two outputs. The typical propagation delay from the driver input to output is 60ns. The driver outputs are current limited to less than 250mA, and can tolerate short circuits to ground, or to any voltage within a +10V to -7V range with no damage. CHARGE PUMP... The charge pump is a Sipex-patented design (5,306,954) and uses a unique approach compared to older less-efficient designs. The charge pump still requires four external capacitors, but uses a four-phase voltage shifting technique to attain symmetrical 10V power supplies. Figure 8a shows the waveform found on the positive side of capacitor C2, and Figure 8b shows the negative side of capacitor C2. There is a freerunning oscillator that controls the four phases of the voltage shifting. A description of each phase follows. RS-485, RS-422 Receivers... The differential receivers of the SP332 comply with the RS-485, RS-422 and V.11 standards. The input to the receiver is equipped with a common mode range of +12V to -7V. The input threshold over this range is a minimum of ±200mV. The differential receivers can receive data up to 10Mbps. The typical propagation delay from the receiver input to output is 90ns. Phase 1 -Vss charge storage- During this phase of the clock cycle, the positive side of capacitors C1 and C2 are initially charged to +5V. C1+ is then switched to ground and charge in C1- is transferred to C2-. Since C2+ is connected to +5V, the voltage potential across capacitor C2 is now 10V. SINGLE ENDED DRIVER/RECEIVER... RS-232 (V.28) Drivers... The single-ended drivers and receivers comply the with the RS-232E and V.28 standards. The drivers are inverting transmitters which accept either TTL or CMOS inputs and output the RS232 signals with an inverted sense relative to the input logic levels. Typically, the RS-232 driver output voltage swing is ±9V with no load and is guaranteed to be greater than ±5V under full load. The drivers rely on the V+ and V- voltages generated by the on-chip charge pump to maintain proper RS-232 output levels. With worst case load conditions of 3kΩ and 2500pF, the four RS-232 drivers can still maintain ±5V output levels. The drivers can operate up to 120kbps; the propagation delay from input to output is typically 2µs. TGoddard/SP332/9617R0 Phase 2 -Vss transfer- Phase two of the clock connects the negative terminal of C2 to the Vss storage capacitor and the positive terminal of C2 to ground, and transfers the generated -10V to C3. Simultaneously, the positive side of capacitor C1 is switched to +5V and the negative side is connected to ground. SP332 RS-232/RS-485 Multi-Mode Serial Transceiver 5 © Copyright 2000 Sipex Corporation 50Ω 125Ω 1µF 1µF VCC1 5V V.35 1µF TXD (103) P DX T DX T S W TXC (114) +10V T RXC (115) X RX T RX T V TXD (104) R GND (102) VCC1 1µF RS-232 GND DX DX RX C2– RX OPTIONAL SIGNALS RX –10V A CABLE SHIELD DX T DX B VCC2 A 1µF 1µF GND DX T T R B RX T X V T C2+ RX T AA Y Y T U W AA RX P S SCTE (113) U b) VCC2 5V 50Ω 1µF a) 1µF 1µF = T V.35 RX DX DX 1µF 1µF 1µF 1µF H C E D F NN N L DTR (108) RTS (105) C DSR (107) E CTS (106) DCD (109) TM (142) RDL (140) LLB (141) ISO 2593 34-PIN DTE/DCE INTERFACE CONNECTOR 1µF RS-232 H RX RX DX D DX F DX NN DX N RX L RX ISO 2593 34-PIN DTE/DCE INTERFACE CONNECTOR Figure 8. Charge Pump Waveforms VCC = +5V VCC = +5V C4 +10V + C1 + – C2 – + – VDD Storage Capacitor + C1 VSS Storage Capacitor C3 – VDD Storage Capacitor VSS Storage Capacitor C3 –5V C4 C2 +5V – + – –10V – + VDD Storage Capacitor C1 VSS Storage Capacitor C3 + – –5V C2 C4 + – – + + – –5V VDD Storage Capacitor VSS Storage Capacitor C3 Figure 12. Charge Pump Phase 4 Figure 11. Charge Pump Phase 3 TGoddard/SP332/9617R0 + VCC = +5V + – – – – Figure 10. Charge Pump Phase 2 VCC = +5V C1 + + C2 –5V Figure 9. Charge Pump Phase 1 + C4 +5V – + SP332 RS-232/RS-485 Multi-Mode Serial Transceiver 6 © Copyright 2000 Sipex Corporation Phase 3 -Vdd charge storage- The third phase of the clock is identical to the first phase- the transferred charge in C1 produces -5V in the negative terminal of C1, which is applied to the negative side of capacitor C2. Since C2+ is at +5V, the voltage potential across C2 is 10V. Since both V+ and V- are separately generated from Vcc in a no load condition, V+ and V- will be symmetrical. Older charge pump approaches that generate V- from V+ will show a decrease in the magnitude of V- compared to V+ due to the inherent inefficiencies in the design. The clock rate for the charge pump typically operates at 15kHz. The external capacitors must be 0.1µF with a 16V breakdown rating. Phase 4 -Vdd transfer- The fourth phase of the clock connects the negative terminal of C2 to ground and transfers the generated 10V across C2 to C4, the Vdd storage capacitor. Simultaneously with this, the positive side of capacitor C1 is switched to +5V and the negative side is connected to ground, and the cycle begins again. SP332 TYPICAL OPERATING CIRCUIT RS-232 Mode RS-485 Mode +5V 9 0.1µF 0.1µF 0V 0V C1+ 12 C111 C2+ 13 C224 SEL A 2 SEL B +5V 5 VCC 5 9 V+ SP332 V- 10 0.1µF 0.1µF 14 0.1µF 0.1µF LOOP 23 BACK Vcc +5V TTL/CMOS +5V 12 26 TI1 Vcc 27 TI2 Vcc TTL/CMOS RS-232 TTL/CMOS TX2 7 T2 28 TI3 TTL/CMOS TX3 4 T3 TTL/CMOS RS-232 Vcc TTL/CMOS 400KΩ TTL/CMOS 1 TI4 V+ V- LOOP BACK Vcc TX4 3 T4 26 TI1 27 TI2 RS-232 TTL/CMOS 28 TI3 1 20 0.1µF 23 TX1 6 Vcc TX4 3 T3 TX3 4 RI2 16 R1 19 RX1 RI1 15 R1 TTL/CMOS RS-232 RX2 21 RX3 5KΩ TTL/CMOS 20 RX2 RI2 16 R2 TTL/CMOS RS-232 5KΩ TTL/CMOS 21 RX3 8 RI3 17 R3 22 RX4 GND TTL/CMOS RS-485 RS-485 RS-485 RS-485 RS-485 15KΩ RI1 15 RS-485 15KΩ RI4 18 TTL/CMOS 0.1µF 14 TX2 7 TI4 19 RX1 10 T1 400KΩ RS-232 400KΩ TTL/CMOS SP332 400KΩ TX1 6 T1 400KΩ TTL/CMOS VCC C1- 11 C2+ 13 C224 SEL A 2 SEL B 400KΩ TTL/CMOS C1+ R3 RS-485 15KΩ RI3 17 RS-485 15KΩ SHUT DOWN 25 TTL/CMOS RS-232 5KΩ TTL/CMOS 22 RX4 RI4 18 R4 RS-232 5KΩ 8 GND TGoddard/SP332/9617R0 SHUT DOWN 25 TTL/CMOS SP332 RS-232/RS-485 Multi-Mode Serial Transceiver 7 © Copyright 2000 Sipex Corporation SP332 CONTROL LOGIC CONFIGURATION SEL A SEL B LOOPBACK SHUTDOWN 0 0 1 0 26 TI1 T1 27 TI2 T2 28 TI3 T3 0 1 1 0 TX1 6 TX2 7 26 TI1 T4 19 RX1 R1 20 RX2 R2 21 RX3 R3 28 TI3 R4 SEL A SEL B LOOPBACK SHUTDOWN T3 TX4 3 TX4 3 19 RX1 RI2 16 20 RX2 R1 R2 27 TI2 28 TI3 T1 T2 T3 TX2 7 R3 19 RX1 20 RX2 21 RX3 T4 R1 R2 R3 R4 RI4 18 R3 28 TI3 TX4 3 TX4 3 R4 20 RX2 R1 RI2 16 RI3 17 RI3 17 R3 RI4 18 RI4 18 1 1 0 0 TX1 6 T1 TX2 7 26 TI1 TX1 6 T1 TX2 7 R1 R2 28 TI3 1 TI4 RI1 15 RI1 15 R1 RI2 16 19 RX1 TX4 3 RI1 15 R1 RI2 16 RI2 16 RI3 17 R3 TX3 4 T3 TX4 3 T4 21 RX3 RI3 17 TX3 4 T3 19 RX1 RI2 16 RI1 15 19 RX1 1 0 0 0 TX3 4 T3 19 RX1 RI2 16 TX4 3 TX2 7 TX3 4 RI1 15 TX2 7 TX3 4 T3 TX4 3 21 RX3 22 RX4 26 TI1 T2 21 RX3 22 RX4 R1 TX1 6 T1 27 TI2 T1 TX3 4 RI1 15 19 RX1 0 1 0 0 26 TI1 TX1 6 26 TI1 RI2 16 21 RX3 28 TI3 1 TI4 T4 RI3 17 RI4 18 TX1 6 TX2 7 28 TI3 1 TI4 RI1 15 RI3 17 0 0 0 0 26 TI1 T3 TX3 4 21 RX3 22 RX4 T1 TX2 7 TX3 4 RI1 15 1 1 1 0 TX1 6 26 TI1 T2 28 TI3 1 TI4 TX1 6 T1 27 TI2 1 0 1 0 RI4 18 RI4 18 R3 RI3 17 21 RX3 22 RX4 R4 RI4 18 RI3 17 R3 RI4 18 Receiver Inputs are inactive in Loopback Mode (LOOPBACK = 0) Driver Outputs are Tri-Stated in Loopback Mode (LOOPBACK = 0) Unused Outputs are Tri-Stated TGoddard/SP332/9617R0 SP332 RS-232/RS-485 Multi-Mode Serial Transceiver 8 © Copyright 2000 Sipex Corporation TI4 SEL B TX4 TX3 VCC TX1 TX2 GND C1+ V+ C2+ C1C2V- 1 2 3 4 5 6 7 8 9 10 11 12 13 14 SP332 28 27 26 25 24 23 22 21 20 19 18 17 16 15 TI3 TI2 TI1 SD SEL A LB RX4 RX3 RX2 RX1 RI4 RI3 RI2 RI1 PACKAGE: PLASTIC SMALL OUTLINE (SOIC) DIMENSIONS (Inches) Minimum/Maximum (mm) 0.093/0.104 0.090/0.100 (2.352/2.649) (2.29/2.54) A 0.004/0.012 0.004/0.010 (0.102/0.300) (0.102/0.254) A1 E H 28–PIN B 0.013/0.020 0.015/0.020 (0.330/0.508) (0.38/0.508) D 0.697/0.713 0.720/0.730 (17.70/18.09) (18.24/18.54) E 0.291/0.299 0.395/0.405 (7.402/7.600) (10.03/10.29) e 0.050 BSC BSC 0.050 (1.270 BSC) (1.270 BSC) H 0.394/0.419 0.531/0.545 (10.00/10.64) (13.49/13.84) L 0.016/0.050 0.021/0.041 (0.406/1.270) (0.53/1.04) Ø 00°/8° ˚/8˚ ((0°/8°) 0˚/8˚) D A Ø e TGoddard/SP332/9617R0 B A1 L SP332 RS-232/RS-485 Multi-Mode Serial Transceiver 9 © Copyright 2000 Sipex Corporation ORDERING INFORMATION Model Temperature Range Package Types SP332CT .............................................................................. 0˚C to +70˚C ......................................................................................... 28-Pin SOIC SP332ET ............................................................................. -40˚C to +85˚C ........................................................................................ 28-Pin SOIC Corporation SIGNAL PROCESSING EXCELLENCE Sipex Corporation Headquarters and Sales Office 22 Linnell Circle Billerica, MA 01821 TEL: (978) 667-8700 FAX: (978) 670-9001 e-mail: [email protected] Sales Office 233 South Hillview Drive Milpitas, CA 95035 TEL: (408) 934-7500 FAX: (408) 935-7600 Sipex Corporation reserves the right to make changes to any products described herein. Sipex does not assume any liability arising out of the application or use of any product or circuit described hereing; neither does it convey any license under its patent rights nor the rights of others. TGoddard/SP332/9617R0 SP332 RS-232/RS-485 Multi-Mode Serial Transceiver 10 © Copyright 2000 Sipex Corporation