19-4585; Rev 1; 2/11 70V Fault-Protected, 3.0V to 5.5V, 2Tx/2Rx RS-232 Transceiver The MAX13223E is a +3.0V to +5.5V-powered EIA/TIA232 and V.28 communications interface with fault protection on the RS-232 line interface. This allows shorts of the transmitter outputs and receiver inputs to voltages in the 70V range without adversely affecting the MAX13223E. The MAX13223E achieves 1A supply current using Maxim's AutoShutdownTM feature. The MAX13223E automatically enters a low-power shutdown mode when the RS-232 cable is disconnected or the receivers are inactive. The device turns on again when a valid transition at any receiver input is sensed. A proprietary, highefficiency, dual charge-pump power supply and a low-dropout transmitter combine to deliver true RS-232 performance from a single +3.0V to +5.5V supply. The MAX13223E has two receivers and two drivers and is guaranteed to run at data rates of 250kbps for one transmitter switching while maintaining RS-232 output levels. The MAX13223E operates from input voltages ranging from +3.0V to +5.5V and is available in a 20-pin, 6.5mm x 4.4mm, TSSOP package. The MAX13223E is specified over the -40C to +85C temperature range. Features 70V Fault Protection +3.0V to +5.5V Supply Voltage Overvoltage Current Limiting Current Protection at Transmitter Outputs AutoShutdown 250kbps (Max) Data Rate Low Current Consumption in Shutdown 1A (typ) Thermal Shutdown Protection 8kV IEC 61000-4-2 Contact-Discharge Method -40C to +85C Operating Temperature Range Ordering Information PART TEMP RANGE PIN-PACKAGE MAX13223EEUP+ -40C to +85C 20 TSSOP +Denotes a lead(Pb)-free/RoHS-compliant package. Typical Operating Circuit Applications Automotive VCC Telematics Equipment CBYPASS 0.1F Base Stations Utility Meters Industrial Equipment C1+ VCC V+ C3 C1 C1- Telecomm Equipment V- C2+ POS Terminal Equipment MAX13223E C2 C4 C2- TTL/CMOS INPUTS T1IN T1OUT T2IN T2OUT R1OUT RS-232 OUTPUTS R1IN 5k TTL/CMOS OUTPUTS RS-232 INPUTS R2IN R2OUT 5k EN FORCEON INVALID GND FORCEOFF TO POWERMANAGEMENT UNIT VCC AutoShutdown is a trademark of Maxim Integrated Products, Inc. ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim's website at www.maxim-ic.com. 1 MAX13223E General Description MAX13223E 70V Fault-Protected, 3.0V to 5.5V, 2Tx/2Rx RS-232 Transceiver ABSOLUTE MAXIMUM RATINGS Short-Circuit Duration T1OUT, T2OUT.......................................................Continuous Continuous Power Dissipation (TA = +70C) TSSOP (derate 13.6mW/C above +70C) ................1084mW Operating Temperature Range .......................... -40C to +85C Junction Temperature ..................................................... +150C Storage Temperature Range ............................ -65C to +150C Lead Temperature (soldering, 10s) .................................+300C Soldering Temperature (reflow) .......................................+260C (Voltages referenced to GND.) VCC ...................................................................... -0.3V to +7.0V V+ ..........................................................................-0.3V to +7.0V V- ...........................................................................+0.3V to -7.0V V+ to V- ................................................................................+13V Input Voltages T1IN, T2IN, EN, FORCEON, FORCEOFF ..........-0.3V to +6.0V R1IN, R2IN .......................................................................70V Output Voltages T1OUT, T2OUT ................................................................70V R1OUT, R2OUT, INVALID ......................-0.3V to (VCC + 0.3V) Stresses beyond those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. PACKAGE THERMAL CHARACTERISTICS (Note 1) TSSOP Junction-to-Ambient Thermal Resistance (JA) ........73.8C/W Junction-to-Case Thermal Resistance (JC) ................20C/W Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a fourlayer board. For detailed information on package thermal considerations, refer to www.maxim-ic.com/thermal-tutorial. ELECTRICAL CHARACTERISTICS (VCC = +3.0V to +5.5V, TA = -40C to +85C, unless otherwise noted. Typical values are at VCC = +3.3V, TA = +25C, unless otherwise noted. For VCC = +3.0V to +3.6V, C1 = C2 = C3 = 0.1F, C4 = 1F. For VCC = +4.5V to +5.5V, C1 = 47nF, C2 = C3 = 330nF, C4 = 1F.) (Note 2) PARAMETER Supply Voltage SYMBOL CONDITIONS VCC MIN MAX UNITS 5.5 V 8 15 mA 3.0 AutoShutdown disabled (FORCEON = FORCEOFF = VCC), no load Supply Current TYP Supply Current AutoShutdown IASD FORCEON = GND, FORCEOFF = VCC, R1IN and R2IN idle, T1IN and T2IN idle 1.0 10 A Supply Current Shutdown I SD FORCEOFF = GND 1.0 10 A 0.8 V LOGIC INPUTS Input-Logic Low VT_IN,LO T_IN, EN, FORCEON, FORCEOFF, VCC = +3.3V to +3.6V, +5.0V to +5.5V Input-Logic High VT_IN,HI T_IN, FORCEON, FORCEOFF, EN Transmitter Input Hysteresis Input Leakage Current VCC = +3.3V 2.0 VCC = +5.0V 2.4 VTX,INHYS I IN,LKG V 0.5 T_IN, EN, FORCEON, FORCEOFF V 0.01 1 A 0.05 10 A 0.4 V RECEIVER OUTPUTS Output Leakage Current IRX,OUT,LKG EN = VCC Output-Voltage Low VRX,OUT,LO I OUT = 1.6mA Output-Voltage High VRX,OUT,HI I OUT = -1.0mA 2 VCC 0.6 VCC 0.2 _______________________________________________________________________________________ V 70V Fault-Protected, 3.0V to 5.5V, 2Tx/2Rx RS-232 Transceiver (VCC = +3.0V to +5.5V, TA = -40C to +85C, unless otherwise noted. Typical values are at VCC = +3.3V, TA = +25C, unless otherwise noted. For VCC = +3.0V to +3.6V, C1 = C2 = C3 = 0.1F, C4 = 1F. For VCC = +4.5V to +5.5V, C1 = 47nF, C2 = C3 = 330nF, C4 = 1F.) (Note 2) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS INVALID OUTPUT (AutoShutdown (FORCEON = GND, FORCEOFF = VCC)) Receiver-Input Level to INVALID Output High VRX_IN, Receiver-Input Level to INVALID Output Low VRX_IN, Figure 6a INV_HI INV_LO Positive level Negative level Figure 6a INVALID Output-Voltage Low VRX,INV_LO I OUT = 1.6mA INVALID Output-Voltage High VRX,INV_HI 2.7 I OUT = -1.0mA -2.7 -0.3 V +0.3 V 0.4 V VCC 0.6 V RECEIVER INPUTS Input-Voltage Range Overvoltage Threshold VRX,IN Input Threshold Low VRX,LO Input Threshold High VRX,HI Input Resistance (Note 3) |VRX,OVTHR| RRX,INRES -70 24 28.3 +70 V 32 V VCC = +3.3V 0.6 VCC = +5.0V 0.8 VCC = +3.3V 2.4 VCC = +5.0V 2.4 V V -24V < VR_IN < +24V (Note 3) 3 VCC = V+ = V- = 0V 35 5 250 7 +32V < |VR_IN | < +70V 35 250 k TRANSMITTER OUTPUTS Output-Voltage Swing Output Resistance VO RTX,ROUT Overvoltage Protection Threshold 5 VCC = V+ = V- = 0V, VT_OUT = 2V 300 |VTX,FB | Output Short-Circuit Current ITX,SHORT Overvoltage Current ITX,IFBOUT Output Leakage Current in Shutdown Mode RL = 3k, Figure 4 14 VT_OUT > VTX,FB VT_OUT < -VTX,FB V T_OUT = GND 19 V 80 mA 6 -6 VT_OUT = +12V ITX,LKG 6 450 VT_OUT = -12V, VCC = 0V, or +3V to +5.5V in shutdown mode -150 R1IN, R2IN, T1OUT, T2OUT -70 mA 900 A -80 PROTECTION Overvoltage Protection Range +70 V ESD PROTECTION (Note 4) R1IN, R2IN, T1OUT, T2OUT All Other Pins IEC 6100-4-2 Contact Discharge 8 Human Body Model 8 Human Body Model 2 kV _______________________________________________________________________________________ 3 MAX13223E ELECTRICAL CHARACTERISTICS (continued) MAX13223E 70V Fault-Protected, 3.0V to 5.5V, 2Tx/2Rx RS-232 Transceiver TIMING CHARACTERISTICS (VCC = +3.0V to +5.5V, TA = -40C to +85C, unless otherwise noted. Typical values are at VCC = +3.3V, TA = +25C, unless otherwise noted. For VCC = +3.0V to +3.6V, C1 = C2 = C3 = 0.1F, C4 = 1F. For VCC = +4.5V to +5.5V, C1 = 47nF, C2 = C3 = 330nF, C4 = 1F.) (Note 2) PARAMETER Maximum Data Rate SYMBOL DR CONDITIONS RL = 3k, CL = 1000pF, one transmitter switching, Figure 1 MIN TYP MAX 250 UNITS kbps Receiver Positive or Negative Threshold to INVALID High t INVH VCC = 5V, Figure 6b 1 s Receiver Positive or Negative Threshold to INVALID Low t INVL VCC = 5V, Figure 6b 30 s Receiver Edge to Transmitters Enabled tWU VCC = 5V, Figure 6b 135 s Receiver-Output Enable Time tRX,EN Normal operation 200 ns tRX,DIS Normal operation 200 ns 50 ns 200 ns Receiver-Output Disable Time Receiver Skew |t PRHL - tPRLH| Transmitter Skew |t PTHL - tPTLH| Receiver Propagation Delay Transmitter Propagation Delay t PRHL t PRLH t PTHL t PTLH (Note 5) 0.3 CL = 150pF, Figure 4 s 0.3 0.8 CL = 1nF, RL = 3k, Figure 3 s 0.6 Transmitter Fall Time or Rise Time tR, tF Figure 3 0.3 s Transmitter Time to Exit Shutdown t SHDN Figure 7 100 s Output Recovery Time tTX,REC CL = 1nF, RL = 5k (Note 6) 100 s SROUT VCC = +3.3V, RL = 3k to 7k, TA = +25C, measured from +3V to -3V or -3V to +3V, one transmitter switching, CL = 1nF Transition-Region Slew Rate 6 30 V/s Note 2: All devices are 100% production tested at TA = +85C. Specifications are over -40C to +85C and are guaranteed by design. Note 3: Both receivers will operate over the 70V input range. The input resistance increases with input voltage. The input resistance will increase within 24V |VR_IN| 32V. Note 4: Guaranteed by design, not production tested. Note 5: Transmitter skew is measured at the transmitter zero crosspoints. Note 6: Output recovery time is the delayed time for the transmitter to enter normal operating mode after an overvoltage condition. 4 _______________________________________________________________________________________ 70V Fault-Protected, 3.0V to 5.5V, 2Tx/2Rx RS-232 Transceiver T_IN T_OUT T_IN CL VO T_OUT R_IN R_OUT 15pF RL Figure 1. Driver Test Circuit Figure 2. Receiver Test Circuit Timing Diagrams VCC VCC/2 T_IN 0 VCC/2 tPTHL tPTLH V0 3V 3V 0 0 T_OUT -3V -3V -V0 tF tR Figure 3. Driver Propagation Delay VIH R_IN tR, tF 10ns 1.3V 1.7V VIL tPRHL tPRLH V0H VCC/2 R_OUT VCC/2 V0L Figure 4. Receiver Propagation Delay _______________________________________________________________________________________ 5 MAX13223E Test Circuits Typical Operating Characteristics (TA = +25C, unless otherwise noted.) SLEW RATE vs. LOAD CAPACITANCE TRANSMITTER OUTPUT VOLTAGE vs. LOAD CAPACITANCE 6 VOUT+ 4 MAX13223E toc02 22 MAX13223E toc01 20 18 + SLEW 16 SLEW RATE (V/s) TRANSMITTER OUTPUT VOLTAGE (V) 8 2 0 -2 14 - SLEW 12 10 8 6 -4 VOUT- 4 -6 2 -8 0 1000 2000 3000 4000 5000 1000 0 2000 3000 4000 LOAD CAPACITANCE (pF) LOAD CAPACITANCE (pF) OPERATING SUPPLY CURRENT vs. LOAD CAPACITANCE TRANSMITTER TIME TO EXIT SHUTDOWN 45 40 250kbps 35 30 5000 MAX13223E toc04 MAX13223E toc03 0 SUPPLY CURRENT (mA) MAX13223E 70V Fault-Protected, 3.0V to 5.5V, 2Tx/2Rx RS-232 Transceiver FORCEON = FORCEOFF T2OUT 5V/div 120kbps 25 2V/div 20 20kbps 15 10 T1 TRANSMITTING AT 250kbps T2 TRANSMITTING AT 15.6kbps 5 0 0 1000 2000 3000 T1OUT VCC = +3.3V C1-C4 = 0.1F 4000 5000 40s/div LOAD CAPACITANCE (pF) Pin Configuration TOP VIEW EN 1 20 FORCEOFF C1+ 2 19 VCC V+ 3 18 GND C1- 4 17 T1OUT C2+ 5 C2- 6 16 R1IN MAX13223E V- 7 15 R1OUT 14 FORCEON T2OUT 8 13 T1IN R2IN 9 12 T2IN R2OUT 10 11 INVALID TSSOP 6 _______________________________________________________________________________________ 70V Fault-Protected, 3.0V to 5.5V, 2Tx/2Rx RS-232 Transceiver PIN NAME FUNCTION Receiver Enable Control Input. Drive EN low for normal operation. Drive EN high to force the receiver outputs (R1OUT, R2OUT) into a high-impedance state. Positive Terminal of the Voltage Doubler Charge-Pump Capacitor 1 EN 2 C1+ 3 V+ +5.5V Generated by Charge Pump 4 C1- Negative Terminal of the Voltage Doubler Charge-Pump Capacitor 5 C2+ Positive Terminal of Inverting Charge-Pump Capacitor 6 C2- Negative Terminal of Inverting Charge-Pump Capacitor 7 V- 8 T2OUT -5.5V Generated by Charge Pump RS-232 Transmitter 2 Output 9 R2IN 10 R2OUT RS-232 Receiver 2 Input Receiver 2 Logic Output 11 INVALID Valid Signal Detector Output. INVALID is high if a valid RS-232 level is present on any receiver input. 12 T2IN 13 T1IN Transmitter 2 Logic Input Transmitter 1 Logic Input Active-High FORCEON Input. Drive FORCEON high to override AutoShutdown, keeping transmitters and charge pump on (FORCEOFF must be high). 14 FORCEON 15 R1OUT Receiver 1 Logic Output 16 R1IN RS-232 Receiver 1 Input 17 T1OUT 18 GND 19 VCC 20 FORCEOFF RS-232 Transmitter 1 Output Ground +3.0V to +5.5V Supply Voltage. Bypass VCC with a 0.1F ceramic capacitor located as close to the device as possible. Active-Low FORCEOFF Input. Drive FORCEOFF low to shut down transmitters, receivers, and on-board charge pumps, overriding AutoShutdown and FORCEON. Detailed Description Figure 2 shows the receiver test circuit. Figure 3 shows driver propagation delay and Figure 4 shows receiver propagation delay. Dual Charge-Pump Voltage Converter The MAX13223E internal power supply consists of a dual-mode regulated charge pump that provides output voltages of +5.5V (doubling charge pump) and -5.5V (inverting charge pump), regardless of the input voltage (VCC) over the +3.0V to +5.5V range. The charge pumps operate in a discontinuous mode. If the output voltages are less than 5.5V, the charge pumps are enabled. If the output voltages exceed 5.5V, the charge pumps are disabled. Each charge pump requires a flying capacitor (C1, C2) and a reservoir capacitor (C3, C4) to generate the V+ and V- supplies. RS-232 Transmitters The transmitters are inverting level translators that convert logic levels to EIA/TIA-232/V.28 levels. They guarantee a 250kbps data rate with worst-case loads of 3k in parallel with 1000pF, providing compatibility with PC-to-PC communication software. The MAX13223E can operate at data rates of 250kbps (max). Transmitters can be paralleled to drive multiple receivers. When FORCEOFF is driven to ground, or the AutoShutdown circuitry senses invalid voltage levels at all receiver inputs, the transmitters are disabled and the outputs are forced into a high-impedance state. Figure 5 shows a complete system connection. RS-232 Receivers The MAX13223E's receivers convert RS-232 signals to logic output levels. Both receiver outputs can be threestated using the EN input. In shutdown (FORCEOFF or AutoShutdown), the MAX13223E's receiver outputs are active and asserted low if EN = Low (Table 1). Driving EN high places the receivers' outputs in a high-impedance state. _______________________________________________________________________________________ 7 MAX13223E Pin Description MAX13223E 70V Fault-Protected, 3.0V to 5.5V, 2Tx/2Rx RS-232 Transceiver FORCEOFF a) FORCEON TRANSMITTER ENABLED, INVALID HIGH INVALID +2.7V RECEIVER INPUT POWERMANAGEMENT UNIT OR CPU MAX13223E INDETERMINATE +0.3V 0 AutoShutdown, TRANSMITTER DISABLED, 1A SUPPLY CURRENT -0.3V INDETERMINATE -2.7V TRANSMITTER ENABLED, INVALID HIGH UART RS-232 b) RECEIVER INPUT VOLTAGE (V) +2.7V +0.3V -0.3V INVALID REGION -2.7V VCC Figure 5. Interface Under Control of PMU INVALID OUTPUT (V) Table 1. Receiver Control Truth Table 0 EN OPERATION MODE R_OUT V+ 0 Active (FORCEON), or Active (AutoShutdown) Active VCC 0 Shutdown (FORCEOFF), or Shutdown (AutoShutdown) Active and asserted low 1 Shutdown status is don't care High impedance tINVL tINVH tWU 0 AutoShutdown The MAX13223E achieves 1A supply current with Maxim's AutoShutdown feature, which operates when FORCEON is low and FORCEOFF is high. When the device senses no valid signal levels on both receiver inputs for > 30s (typ), the onboard charge pump and drivers are shut off, reducing supply current to 1A. This occurs if the RS-232 cable is disconnected or the connected peripheral transmitters are turned off. The device turns on again when a valid level is applied to either RS-232 receiver input. As a result, the system saves power. Table 2 summarizes the MAX13223E's operating modes. FORCEON and FORCEOFF override 8 V- Figures 6a and 6b. Trip Levels for Entering and Exiting AutoShutdown AutoShutdown. When neither control is asserted, the IC selects between these states automatically, based on receiver input levels. Figure 6a shows the input levels and Figure 6b shows the timing diagram for AutoShutdown operation. Software-Controlled Shutdown If direct software control is desired, INVALID can be used to indicate a DTR or Ring indicator signal. Connect FORCEOFF and FORCEON together to bypass AutoShutdown; therefore, the line acts as a SHDN input. _______________________________________________________________________________________ 70V Fault-Protected, 3.0V to 5.5V, 2Tx/2Rx RS-232 Transceiver MAX13223E Table 2. AutoShutdown Control INPUTS OUTPUTS INVALID OUTPUT OPERATION MODE T_OUT 0 Shutdown (Forced Off) High-Z FORCEOFF FORCEON VALID RECEIVER INPUT LEVEL 0 X No 0 X Yes 1 Shutdown (Forced Off) High-Z 1 0 No 0 Shutdown (AutoShutdown) High-Z 1 0 Yes 1 Active (AutoShutdown) Active 1 1 No 0 Active (Forced On) Active 1 1 Yes 1 Active (Forced On) Active X = Don't Care. Applications Information Capacitor Selection The capacitor type used for C1-C4 is not critical for proper operation; either polarized or nonpolarized capacitors may be used. The charge pump requires 0.1F capacitors for 3.3V operation. For other supply voltages, see Table 3 for required capacitor values. Do not use values smaller than those listed in Table 3. Increasing the capacitor values (e.g., by a factor of 2) reduces ripple on the transmitter outputs and slightly reduces power consumption. C2, C3, and C4 can be increased without changing C1's value. However, do not increase C1 without also increasing the values of C2, C3, and C4 to maintain the proper ratios (C1 to the other capacitors). When using the minimum required capacitor values, make sure the capacitor value does not degrade excessively with temperature. If in doubt, use capacitors with a larger nominal value. The capacitor's equivalent series resistance (ESR) usually rises at low temperatures and influences the amount of ripple on V+ and V-. Table 3. Required Capacitor Values VCC (V) C1, CBYPASS (F) C2, C3 (F) C4 (F) 3.0 to 3.6 0.1 0.1 1 4.5 to 5.5 0.047 0.33 1 Power-Supply Decoupling Transmitter Outputs when Exiting Shutdown Figure 7 shows two transmitter outputs when exiting shutdown mode. As they become active, the two transmitter outputs are shown going to opposite RS-232 levels. Each transmitter is loaded with 3k in parallel with 2500pF. The transmitter outputs display no ringing or undesirable transients as they come out of shutdown. Note that the transmitters are enabled only when the magnitude of V- exceeds approximately 3V. FORCEON = FORCEOFF T2OUT 5V/div 2V/div T1OUT VCC = +3.3V C1-C4 = 0.1F 40s/div Figure 7. Transmitter Outputs when Exiting Shutdown or Powering Up In most circumstances, a 0.1F VCC bypass capacitor is adequate. In applications that are sensitive to power-supply noise, decouple VCC to ground with a capacitor of the same value as the charge-pump capacitor C1. Connect bypass capacitors as close to the IC as possible. _______________________________________________________________________________________ 9 MAX13223E 70V Fault-Protected, 3.0V to 5.5V, 2Tx/2Rx RS-232 Transceiver Fault Protection The MAX13223E is designed to survive faults such as direct shorts to power supplies, miswiring faults, connector failures, and tool misapplications of the transmitter outputs and receiver inputs to voltages in the 70V range without damage. This fault protection is applicable in all modes of the MAX13223E: active, shutdown, and powered down. Both receivers operate over the 70V input range, but the termination resistor (RRX,I) increases when |V R_IN | voltage exceeds 32V. A receiver's input termination resistor reduces to its nominal value if the input voltage reduces to within the 24V range. The receiver inputs and transmitter outputs are independently fault protected. RC 1M CHARGE-CURRENT LIMIT RESISTOR HIGHVOLTAGE DC SOURCE Cs 100pF RD 1500 DISCHARGE RESISTANCE DEVICE UNDER TEST STORAGE CAPACITOR Figure 8a. Human Body ESD Test Model 8kV ESD Protection As with all Maxim devices, ESD-protection structures are incorporated on all pins to protect against electrostatic discharges encountered during handling and assembly. In using the MAX13223E, C4 must be a 1F capacitor for the extended ESD protection. The driver outputs and receiver inputs of the MAX13223E have extra protection against static electricity. Maxim's engineers have developed state-of-the-art structures to protect these pins against ESD of 8kV without damage. The ESD structures withstand high ESD in all states: normal operation, shutdown, and powered down. After an ESD event, Maxim's E versions keep working without latchup, whereas competing RS-232 products can latch and must be powered down to remove latchup. ESD protection can be tested in various ways. The transmitter outputs and receiver inputs of this product family are characterized for protection to the following limits: 1) 8kV using the Human Body Model 2) 8kV using the Contact-Discharge Method specified in IEC 61000-4-2 ESD Test Conditions ESD performance depends on a variety of conditions. Contact Maxim for a reliability report that documents test setup, test methodology, and test results. Human Body Model Figure 8a shows the Human Body Model and Figure 8b shows the current waveform it generates when discharged into a low impedance. This model consists of a 100pF capacitor charged to the ESD voltage of interest, which is then discharged into the test device through a 1.5k resistor. 10 IP 100% 90% Ir PEAK-TO-PEAK RINGING (NOT DRAWN TO SCALE) AMPERES 36.8% 10% 0 0 tRL TIME tDL CURRENT WAVEFORM Figure 8b. Human Body Current Waveform IEC 61000-4-2 The IEC 61000-4-2 standard covers ESD testing and performance of finished equipment. It does not specifically refer to integrated circuits. The major difference between tests done using the Human Body Model and IEC 61000-4-2 is higher peak current in IEC 61000-4-2, because series resistance is lower in the IEC 61000-4-2 model. Hence, the ESD withstand voltage measured to IEC 61000-4-2 is generally lower than that measured using the Human Body Model. Figure 9a shows the IEC 61000-4-2 model and Figure 9b shows the current waveform for the 8kV, IEC 61000-4-2, level 4, ESD Contact-Discharge Method. ______________________________________________________________________________________ 70V Fault-Protected, 3.0V to 5.5V, 2Tx/2Rx RS-232 Transceiver PROCESS: CMOS DISCHARGE RESISTANCE CHARGE CURRENT LIMIT RESISTOR HIGHVOLTAGE DC SOURCE Chip Information RD 330 Cs 150pF STORAGE CAPACITOR Package Information DEVICE UNDER TEST Figure 9a. IEC 61000-4-2 ESD Test Model For the latest package outline information and land patterns (footprints), go to www.maxim-ic.com/packages. Note that a "+", "#", or "-" in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. PACKAGE TYPE PACKAGE CODE OUTLINE NO. LAND PATTERN NO. 20 TSSOP U20+2 21-0066 90-0116 I 100% I PEAK 90% 10% t r = 0.7ns to 1ns t 30ns 60ns Figure 9b. IEC 61000-4-2 ESD Generator Current Waveform ______________________________________________________________________________________ 11 MAX13223E RC 50M to 100M MAX13223E 70V Fault-Protected, 3.0V to 5.5V, 2Tx/2Rx RS-232 Transceiver Revision History REVISION NUMBER REVISION DATE 0 4/09 Initial release 2/11 Added soldering information to the Absolute Maximum Ratings section; updated the Electrical Characteristics globals information for C1 = C2 = C3 = 0.1F and C2 = C3 = 330nF; corrected the reference of V OUT to VT_OUT for the overvoltage current parameter in the Electrical Characteristics table; added R_OUT to Figure 2; updated the RS-232 Receivers section description and Table 1; added the land pattern no. to the Package Information table 1 DESCRIPTION PAGES CHANGED 2, 3, 4, 5, 7, 8, 11 Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. 12 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 (c) 2011 Maxim Integrated Products Maxim is a registered trademark of Maxim Integrated Products, Inc.