MAX13223E

19-4585; Rev 0; 4/09 ±70V Fault-Protected, 3.0V to 5.5V, 2Tx/2Rx RS-232 Transceiver General Description 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 1µA supply current using Maxim’s AutoShutdown™ 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 -40°C to +85°C temperature range. o ±70V Fault Protection o +3.0V to +5.5V Supply Voltage o Overvoltage Current Limiting o Current Protection at Transmitter Outputs o AutoShutdown o 250kbps (Max) Data Rate o Low Current Consumption in Shutdown 1µA (typ) o Thermal Shutdown Protection o ±8kV IEC 61000-4-2 Contact-Discharge Method o -40°C to +85°C Operating Temperature Range Features MAX13223E Ordering Information PART MAX13223EEUP+ TEMP RANGE -40°C to +85°C PIN-PACKAGE 20 TSSOP +Denotes a lead(Pb)-free/RoHS-compliant package. Applications Automotive Telematics Equipment Base Stations Utility Meters Industrial Equipment Telecomm Equipment POS Terminal Equipment C2 Typical Operating Circuit VCC CBYPASS 0.1µF VCC C1+ C1 C1C2+ V+ C3 V- MAX13223E C2T1IN T1OUT C4 TTL/CMOS INPUTS T2IN T2OUT RS-232 OUTPUTS R1OUT R1IN 5kΩ AutoShutdown is a trademark of Maxim Integrated Products, Inc. TTL/CMOS OUTPUTS R2OUT RS-232 INPUTS R2IN 5kΩ Typical Operating Circuit appears at end of data sheet. EN INVALID TO POWERMANAGEMENT UNIT VCC FORCEON GND FORCEOFF ________________________________________________________________ Maxim Integrated Products 1 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. ±70V Fault-Protected, 3.0V to 5.5V, 2Tx/2Rx RS-232 Transceiver MAX13223E ABSOLUTE MAXIMUM RATINGS (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) Short-Circuit Duration T1OUT, T2OUT.......................................................Continuous Continuous Power Dissipation (TA = +70°C) 20-Pin TSSOP (derate 13.6mW/°C above +70°C) .....1084mW Junction-to-Case Thermal Resistance (θJC) (Note 1) 20-Pin TSSOP...............................................................20°C/W Junction-to-Ambient Thermal Resistance (θJA) (Note 1) 20-Pin TSSOP............................................................73.8°C/W Operating Temperature Range .......................... -40°C to +85°C Junction Temperature ..................................................... +150°C Storage Temperature Range ............................ -65°C to +150°C Lead Temperature (soldering, 10s) .................................+300°C 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. 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. ELECTRICAL CHARACTERISTICS (VCC = +3.0V to +5.5V, TA = -40°C to +85°C, unless otherwise noted. Typical values are at VCC = +3.3V, TA = +25°C, unless otherwise noted. For VCC = +3.0V to +3.6V, C1–C3 = 0.1µF, C4 = 1µF. For VCC = +4.5V to +5.5V, C1 = 47nF, C2–C3 = 330nF, C4 = 1µF.) (Note 2) PARAMETER Supply Voltage Supply Current Supply Current AutoShutdown Supply Current Shutdown LOGIC INPUTS Input-Logic Low Input-Logic High Transmitter Input Hysteresis Input Leakage Current RECEIVER OUTPUTS Output Leakage Current Output-Voltage Low Output-Voltage High IRX,OUT,LKG EN = VCC VRX,OUT,LO IOUT = 1.6mA VRX,OUT,HI IOUT = -1.0mA VCC 0.6 Positive level Negative level 2.7 -2.7 VCC 0.2 ±0.05 ±10 0.4 µA V V VT_IN,LO VT_IN,HI VTX,INHYS IIN,LKG T_IN, EN, FORCEON, FORCEOFF T_IN, EN, FORCEON, FORCEOFF, VCC = +3.3V to +3.6V, +5.0V to +5.5V T_IN, FORCEON, FORCEOFF, EN VCC = +3.3V VCC = +5.0V 2.0 2.4 0.5 ±0.01 ±1 0.8 V V V µA IASD ISD SYMBOL VCC AutoShutdown disabled (FORCEON = FORCEOFF = VCC), no load FORCEON = GND, FORCEOFF = VCC, R1IN and R2IN idle, T1IN and T2IN idle FORCEOFF = GND CONDITIONS MIN 3.0 8 1.0 1.0 TYP MAX 5.5 15 10 10 UNITS V mA µA µA INVALID OUTPUT (AutoShutdown (FORCEON = GND, FORCEOFF = VCC)) Receiver-Input Level to INVALID Output High VRX_IN, INV_HI Figure 6a V 2 _______________________________________________________________________________________ ±70V Fault-Protected, 3.0V to 5.5V, 2Tx/2Rx RS-232 Transceiver ELECTRICAL CHARACTERISTICS (continued) (VCC = +3.0V to +5.5V, TA = -40°C to +85°C, unless otherwise noted. Typical values are at VCC = +3.3V, TA = +25°C, unless otherwise noted. For VCC = +3.0V to +3.6V, C1–C3 = 0.1µF, C4 = 1µF. For VCC = +4.5V to +5.5V, C1 = 47nF, C2–C3 = 330nF, C4 = 1µF.) (Note 2) PARAMETER Receiver-Input Level to INVALID Output Low INVALID Output-Voltage Low INVALID Output-Voltage High RECEIVER INPUTS Input-Voltage Range Overvoltage Threshold Input Threshold Low Input Threshold High VRX,IN |VRX,OVTHR| VRX,LO VRX,HI VCC = +3.3V VCC = +5.0V VCC = +3.3V VCC = +5.0V -24V < VR_IN < +24V (Note 3) Input Resistance TRANSMITTER OUTPUTS Output-Voltage Swing Output Resistance Overvoltage Protection Threshold Output Short-Circuit Current Overvoltage Current Output Leakage Current in Shutdown Mode PROTECTION Overvoltage Protection Range ESD PROTECTION (Note 4) R1IN, R2IN, T1OUT, T2OUT All Other Pins IEC 6100-4-2 Contact Discharge Human Body Model Human Body Model ±8 ±8 ±2 kV R1IN, R2IN, T1OUT, T2OUT -70 +70 V VO RTX,ROUT |VTX,FB| ITX,SHORT ITX,IFBOUT T_OUT = 0 VOUT > VTX,FB VOUT < -VTX,FB T_OUT = +12V ITX,LKG T_OUT = -12V, VCC = 0 or 3V to 5.5V in shutdown mode -150 -6 450 -80 900 µA RL = 3kΩ, Figure 4 VCC = V+ = V- = 0, TOUT = ±2V ±5 300 14 19 ±80 6 ±6 V Ω V mA mA RRX,INRES VCC = V+ = V- = 0 +32V < |VR_IN| < +70V 2.4 2.4 3 35 35 5 7 250 250 kΩ (Note 3) -70 24 28.3 +70 32 0.6 0.8 V V V V SYMBOL VRX_IN, INV_LO MAX13223E CONDITIONS Figure 6a MIN -0.3 TYP MAX +0.3 0.4 UNITS V V V VRX,INV_LO IOUT = 1.6mA VRX,INV_HI IOUT = -1.0mA VCC 0.6 _______________________________________________________________________________________ 3 ±70V Fault-Protected, 3.0V to 5.5V, 2Tx/2Rx RS-232 Transceiver MAX13223E TIMING CHARACTERISTICS (VCC = +3.0V to +5.5V, TA = -40°C to +85°C, unless otherwise noted. Typical values are at VCC = +3.3V, TA = +25°C, unless otherwise noted. For VCC = +3.0V to +3.6V, C1–C3 = 0.1µF, C4 = 1µF. For VCC = +4.5V to +5.5V, C1 = 47nF, C2–C3 = 330nF, C4 = 1µF.) (Note 2) PARAMETER Maximum Data Rate Receiver Positive or Negative Threshold to INVALID High Receiver Positive or Negative Threshold to INVALID Low Receiver Edge to Transmitters Enabled Receiver-Output Enable Time Receiver-Output Disable Time Receiver Skew Transmitter Skew Receiver Propagation Delay Transmitter Propagation Delay Transmitter Fall Time or Rise Time Transmitter Time to Exit Shutdown Output Recovery Time Transition-Region Slew Rate SYMBOL DR tINVH tINVL tWU tRX,EN tRX,DIS |tPRHL - tPRLH| |tPTHL - tPTLH| tPRHL tPRLH tPTHL tPTLH tR, tF tSHDN tTX,REC SROUT (Note 5) CL = 150pF, Figure 4 CL = 1nF, RL = 3kΩ, Figure 3 Figure 3 Figure 7 CL = 1nF, RL = 5kΩ (Note 6) VCC = 3.3V, RL = 3kΩ to 7kΩ, TA = +25°C, measured from +3V to -3V or -3V to +3V, one transmitter switching, CL = 1nF 6 CONDITIONS RL = 3kΩ, CL = 1000pF, one transmitter switching, Figure 1 VCC = 5V, Figure 6b VCC = 5V, Figure 6b VCC = 5V, Figure 6b Normal operation Normal operation MIN 250 1 30 135 200 200 50 200 0.3 0.3 0.8 0.6 0.3 100 100 30 TYP MAX UNITS kbps µs µs µs ns ns ns ns µs µs µs µs µs V/µs Note 2: All devices are 100% production tested at TA = +85°C. Specifications are over -40°C to +85°C 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 Test Circuits T_IN T_OUT T_IN T_OUT R_IN MAX13223E VO CL RL 15pF Figure 1. Driver Test Circuit Figure 2. Receiver Test Circuit Timing Diagrams VCC T_IN 0 V0 3V T_OUT -V0 tF tR 0 -3V -3V 0 VCC/2 tPTHL VCC/2 tPTLH 3V Figure 3. Driver Propagation Delay VIH R_IN VIL tPRHL V0H R_OUT V0L VCC/2 VCC/2 tPRLH 1.3V tR, tF ≤ 10ns 1.7V Figure 4. Receiver Propagation Delay _______________________________________________________________________________________ 5 ±70V Fault-Protected, 3.0V to 5.5V, 2Tx/2Rx RS-232 Transceiver MAX13223E Typical Operating Characteristics (TA = +25°C, unless otherwise noted.) TRANSMITTER OUTPUT VOLTAGE vs. LOAD CAPACITANCE MAX13223E toc01 SLEW RATE vs. LOAD CAPACITANCE 20 18 16 SLEW RATE (V/µs) 14 12 10 8 6 4 2 0 - SLEW + SLEW MAX13223E toc02 OPERATING SUPPLY CURRENT vs. LOAD CAPACITANCE 40 35 SUPPLY CURRENT (mA) 30 25 20 15 10 5 0 T1 TRANSMITTING AT 250kbps T2 TRANSMITTING AT 15.6kbps 0 1000 2000 3000 4000 5000 20kbps 120kbps 250kbps MAX13223E toc03 8 TRANSMITTER OUTPUT VOLTAGE (V) 6 VOUT+ 4 2 0 -2 -4 -6 -8 0 1000 2000 3000 4000 VOUT- 22 45 5000 0 1000 2000 3000 4000 5000 LOAD CAPACITANCE (pF) LOAD CAPACITANCE (pF) LOAD CAPACITANCE (pF) TRANSMITTER TIME TO EXIT SHUTDOWN MAX13223E toc04 5V/div FORCEON = FORCEOFF T2OUT 2V/div VCC = +3.3V C1–C4 = 0.1µF 40µs/div T1OUT 6 _______________________________________________________________________________________ ±70V Fault-Protected, 3.0V to 5.5V, 2Tx/2Rx RS-232 Transceiver Pin Description PIN 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 NAME EN C1+ V+ C1C2+ C2VT2OUT R2IN R2OUT INVALID T2IN T1IN FORCEON R1OUT R1IN T1OUT GND VCC FORCEOFF 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 +5.5V Generated by Charge Pump Negative Terminal of the Voltage Doubler Charge-Pump Capacitor Positive Terminal of Inverting Charge-Pump Capacitor Negative Terminal of Inverting Charge-Pump Capacitor -5.5V Generated by Charge Pump RS-232 Transmitter 2 Output RS-232 Receiver 2 Input Receiver 2 Logic Output Valid Signal Detector Output. INVALID is high if a valid RS-232 level is present on any receiver input. 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). Receiver 1 Logic Output RS-232 Receiver 1 Input RS-232 Transmitter 1 Output Ground +3.0V to +5.5V Supply Voltage. Bypass VCC with a 0.1µF 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. MAX13223E Detailed Description Figure 2 shows the receiver test circuit. Figure 3 shows driver propagation delay and Figure 4 shows receiver propagation delay. 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 3kΩ 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. 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 Receivers The MAX13223E’s receivers convert RS-232 signals to logic output levels. Both receiver outputs can be tristated using the EN input. In shutdown (FORCEOFF = low) or in AutoShutdown, the MAX13223E’s receivers are active (Table 1). Driving E N high places the receivers’ outputs in a high-impedance state. 7 _______________________________________________________________________________________ ±70V Fault-Protected, 3.0V to 5.5V, 2Tx/2Rx RS-232 Transceiver MAX13223E FORCEOFF POWERMANAGEMENT UNIT OR CPU FORCEON INVALID RECEIVER INPUT TRANSMITTER ENABLED, INVALID HIGH +2.7V INDETERMINATE +0.3V 0 -0.3V INDETERMINATE -2.7V TRANSMITTER ENABLED, INVALID HIGH AutoShutdown, TRANSMITTER DISABLED, 1µA SUPPLY CURRENT a) MAX13223E UART RS-232 b) RECEIVER INPUT VOLTAGE (V) +2.7V +0.3V -0.3V -2.7V VCC INVALID REGION Figure 5. Interface Under Control of PMU INVALID OUTPUT (V) 0 tINVL tINVH tWU Table 1. Receiver Control Truth Table EN 0 1 R_OUT Active High Impedence V+ VCC 0 V- AutoShutdown The MAX13223E achieves 1µA 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 > 30µs (typ), the onboard charge pump and drivers are shut off, reducing supply current to 1µA. 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 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. 8 _______________________________________________________________________________________ ±70V Fault-Protected, 3.0V to 5.5V, 2Tx/2Rx RS-232 Transceiver MAX13223E Table 2. AutoShutdown Control INPUTS FORCEOFF 0 0 1 1 1 1 FORCEON X X 0 0 1 1 VALID RECEIVER INPUT LEVEL No Yes No Yes No Yes INVALID OUTPUT 0 1 0 1 0 1 OUTPUTS OPERATION MODE Shutdown (Forced Off) Shutdown (Forced Off) Shutdown (AutoShutdown) Active (AutoShutdown) Active (Forced On) Active (Forced On) T_OUT High-Z High-Z High-Z Active Active 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 0.1µF 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-. 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 3kΩ 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. 5V/div FORCEON = FORCEOFF T2OUT 2V/div Table 3. Required Capacitor Values VCC (V) 3.0 to 3.6 4.5 to 5.5 C1, CBYPASS (µF) 0.1 0.047 C2, C3 (µF) 0.1 0.33 C4 (µF) 1 1 VCC = +3.3V C1–C4 = 0.1µF 40µs/div T1OUT Power-Supply Decoupling In most circumstances, a 0.1µF 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. Figure 7. Transmitter Outputs when Exiting Shutdown or Powering Up _______________________________________________________________________________________ 9 ±70V Fault-Protected, 3.0V to 5.5V, 2Tx/2Rx RS-232 Transceiver MAX13223E 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 1MΩ CHARGE-CURRENT LIMIT RESISTOR HIGHVOLTAGE DC SOURCE RD 1500Ω DISCHARGE RESISTANCE DEVICE UNDER TEST Cs 100pF 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 1µF 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 IP 100% 90% AMPERES 36.8% 10% 0 0 tRL TIME tDL CURRENT WAVEFORM Ir PEAK-TO-PEAK RINGING (NOT DRAWN TO SCALE) 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. 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 1.5kΩ resistor. 10 ______________________________________________________________________________________ ±70V Fault-Protected, 3.0V to 5.5V, 2Tx/2Rx RS-232 Transceiver RC 50MΩ to 100MΩ CHARGE CURRENT LIMIT RESISTOR HIGHVOLTAGE DC SOURCE RD 330Ω DISCHARGE RESISTANCE DEVICE UNDER TEST Pin Configuration TOP VIEW EN 1 C1+ 2 V+ 3 C1- 4 C2+ 5 C2- 6 20 FORCEOFF 19 VCC 18 GND 17 T1OUT 16 R1IN MAX13223E Cs 150pF STORAGE CAPACITOR MAX13223E 15 R1OUT 14 FORCEON 13 T1IN 12 T2IN 11 INVALID Figure 9a. IEC 61000-4-2 ESD Test Model V- 7 T2OUT 8 I 100% 90% R2IN 9 R2OUT 10 TSSOP I PEAK 10% t r = 0.7ns to 1ns t 60ns Chip Information PROCESS: CMOS 30ns Figure 9b. IEC 61000-4-2 ESD Generator Current Waveform Package Information For the latest package outline information and land patterns, go to www.maxim-ic.com/packages. PACKAGE TYPE 20 TSSOP PACKAGE CODE U20+2 DOCUMENT NO. 21-0066 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. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 11 © 2009 Maxim Integrated Products Maxim is a registered trademark of Maxim Integrated Products, Inc.