MAX3311ECUB

19-1910; Rev 0; 1/01 ±15kV ESD-Protected, 460kbps, 1µA, RS-232-Compatible Transceivers in µMAX The MAX3311E/MAX3313E are low-power, 5V EIA/TIA232-compatible transceivers. All transmitter outputs and receiver inputs are protected to ±15kV using the Human Body Model, making these devices ideal for applications where more robust transceivers are required. Both devices have one transmitter and one receiver. The transmitters have a proprietary low-dropout transmitter output stage enabling RS-232-compatible operation from a +5V supply with a single inverting charge pump. These transceivers require only three 0.1µF capacitors and will run at data rates up to 460kbps while maintaining RS-232-compatible output levels. The MAX3311E features a 1µA shutdown mode. In shutdown the device turns off the charge pump, pulls V- to ground, and the transmitter output is disabled. The MAX3313E features an INVALID output that asserts high when an active RS-232 cable signal is connected, signaling to the host that a peripheral is connected to the communication port. Features ♦ ESD Protection for RS-232-Compatible I/O Pins ±15kV—Human Body Model ♦ 1µA Low-Power Shutdown (MAX3311E) ♦ INVALID Output (MAX3313E) ♦ Receiver Active in Shutdown (MAX3311E) ♦ Single Transceiver (1Tx/1Rx) in 10-Pin µMAX Package Ordering Information PART MAX3311ECUB TEMP. RANGE 0°C to +70°C PIN-PACKAGE 10 µMAX MAX3311EEUB -40°C to +85°C 10 µMAX MAX3313ECUB 0°C to +70°C 10 µMAX MAX3313EEUB -40°C to +85°C 10 µMAX ________________________Applications Digital Cameras PDAs Typical Operating Circuit GPS POS +5V Telecommunications CBYPASS 0.1µF Handy Terminals 1 9 Set-Top Boxes C1 0.1µF 2 C1+ VCC V- 8 C2 0.1µF C1- Pin Configurations MAX3311E MAX3313E 4 TIN TOUT 7 TOP VIEW RIN 6 5 ROUT VCC 1 10 GND C1- 2 9 C1+ SHDN 3 8 V- TIN 4 7 TOUT ROUT 5 6 RIN 5k MAX3311E SHDN (MAX3311E) 3 INVALID (MAX3313E) GND 10 µMAX CAPACITORS MAY BE POLARIZED OR NONPOLARIZED. Pin Configurations continued at end of data sheet. ________________________________________________________________ Maxim Integrated Products 1 For price, delivery, and to place orders, please contact Maxim Distribution at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. MAX3311E/MAX3313E General Description MAX3311E/MAX3313E ±15kV ESD-Protected, 460kbps, 1µA, RS-232-Compatible Transceivers in µMAX ABSOLUTE MAXIMUM RATINGS VCC to GND .............................................................-0.3V to +6V V- to GND ................................................................+0.3V to -7V VCC + |V-| ............................................................................+13V Input Voltages TIN, SHDN to GND ...............................................-0.3V to +6V RIN to GND ......................................................................±25V Output Voltages TOUT to GND................................................................±13.2V ROUT, INVALID to GND .....................…-0.3V to (VCC + 0.3V) Short-Circuit Duration TOUT to GND .........................................................Continuous Continuous Power Dissipation 10-Pin µMAX (derate 5.6mW/°C above +70°C) ..........444mW Operating Temperature Ranges MAX331_ECUB .................................................0°C to +70°C MAX331_EEUB ..............................................-40°C to +85°C Junction Temperature .....................................................+150°C Storage Temperature Range ............................-65°C to +150°C Lead Temperature (soldering, 10s) ................................+300°C 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 = +5V, C1 and C2 = 0.1µF, TA = TMIN to TMAX. Typical values are at TA = +25°C.) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS DC CHARACTERISTICS Supply Operation Range VCC 4.5 Supply Current SHDN = VCC, no load Shutdown Supply Current SHDN = GND (MAX3311E only) 5 5.5 V 100 250 µA 1 10 µA LOGIC INPUTS (TIN, SHDN) Input Logic Threshold Low VIL Input Logic Threshold High VIH 0.8 Transmitter Input Hysteresis V 2.4 V ±1 µA 0.4 V 0.5 ±0.01 Input Leakage Current V RECEIVER OUTPUT Output Voltage Low VOL IOUT = 1.6mA Output Voltage High VOH IOUT = -1.0mA VCC - 0.6 VCC - 0.1 V INVALID OUTPUT (MAX3313E only) Figure 7, positive threshold Receiver Input Threshold to INVALID Output High Receiver Input Threshold to INVALID Output Low 2 2.7 Figure 7, negative threshold -2.7 Figure 7 -0.3 INVALID Output Low VOL IOUT = 1.6mA INVALID Output High VOH IOUT = -1.0mA 0.3 0.4 VCC - 0.6 V V V V Receiver Positive or Negative Thresholds to INVALID High Figure 7 0.1 µs Receiver Positive or Negative Threshold to INVALID Low Figure 7 30 µs _______________________________________________________________________________________ ±15kV ESD-Protected, 460kbps, 1µA, RS-232-Compatible Transceivers in µMAX (VCC = +5V, C1 and C2 = 0.1µF, TA = TMIN to TMAX. Typical values are at TA = +25°C.) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS RECEIVER INPUT Input Threshold Low VIL Input Threshold High VIH 0.8 V 2.4 V Input Hysteresis 0.5 V Input Resistance 5 kΩ TRANSMITTER OUTPUT Output Voltage Swing Transmitter output loaded with 3kΩ to ±3.7 V Output Resistance (Note 1) VCC = 0, transmitter output = ±2V 300 Ω Output Short-Circuit Current VOUT = ±12V, transmitter disabled Output Leakage Current ±60 mA ±25 µA ESD PERFORMANCE (TRANSMITTER OUTPUT, RECEIVER INPUT) ESD-Protection Voltage ±15 Human Body Model kV Note 1: Not tested—guaranteed by design. TIMING CHARACTERISTICS (VCC = +5V, C1 and C2 = 0.1µF, TA = TMIN to TMAX. Typical values are at TA = +25°C.) PARAMETER SYMBOL Maximum Data Rate CONDITIONS RL = 3kΩ, CL = 1000pF Receiver input to receiver output, CL = 150pF MIN TYP 460 MAX UNITS kbps 0.15 µs Transmitter Skew 100 ns Receiver Skew 50 ns 11 V/µs Receiver Propagation Delay Transition Region Slew Rate tPLH/tPHL RL = 3kΩ to 7kΩ, CL = 150pF to 1000pF, measured from +3V to -3V or from -3V to +3V _______________________________________________________________________________________ 3 MAX3311E/MAX3313E ELECTRICAL CHARACTERISTICS (continued) Typical Operating Characteristics (VCC = +5V, 0.1µF capacitors, transmitter loaded with 3kΩ and CL, TA = +25°C, unless otherwise noted.) 8 -SLEW 6 4 2 5 4 3 460kbps/250kbps/120kbps 2 1 0 -1 -2 460kbps/250kbps/120kbps -3 460kbps 12 SUPPLY CURRENT (mA) +SLEW 14 MAX3311E/13E-02 12 TRANSMITTER OUTPUT VOLTAGE (V) 250 kbps DATA RATE 10 6 MAX3311E/13E-01 14 SUPPLY CURRENT vs. LOAD CAPACITANCE TRANSMITTER OUTPUT VOLTAGE vs. LOAD CAPACITANCE 250kbps 10 MAX3311E/13E-03 SLEW RATE vs. LOAD CAPACITANCE SLEW RATE (V/µs) MAX3311E/MAX3313E ±15kV ESD-Protected, 460kbps, 1µA, RS-232-Compatible Transceivers in µMAX 120kbps 8 20kbps 6 4 2 -4 0 0 -5 0 500 1000 1500 2000 2500 3000 0 LOAD CAPACITANCE (pF) 500 1000 1500 2000 2500 3000 0 500 1000 1500 2000 2500 3000 LOAD CAPACITANCE (pF) LOAD CAPACITANCE (pF) Pin Description PIN 4 NAME FUNCTION MAX3311E MAX3313E 1 1 VCC +5V External Power Supply. Decouple with a 0.1µF capacitor to ground. 2 2 C1- Negative Terminal of the Voltage Inverter Charge-Pump Capacitor 3 — SHDN — 3 INVALID 4 4 TIN TTL/CMOS Transmitter input 5 5 ROUT TTL/CMOS Receiver output 6 6 RIN 7 7 TOUT 8 8 V- 9 9 C1+ Positive Terminal of the Voltage Inverter Charge-Pump Capacitor 10 10 GND Ground Shutdown Active Low (0 = off, 1 = on) Valid Signal Detector Output, Active Low. A logic high indicates that a valid RS-232 level is present on the receiver input. ±15kV ESD-Protected, RS-232 Receiver Input ±15kV ESD-Protected, RS-232-Compatible Transmitter Output -4.3V generated by the charge pump. Connect a 0.1µF capacitor to ground. _______________________________________________________________________________________ ±15kV ESD-Protected, 460kbps, 1µA, RS-232-Compatible Transceivers in µMAX Single Charge-Pump Voltage Converter The MAX3311E/MAX3313E internal power supply has a single inverting charge pump that provides a negative voltage from a single +5V supply. The charge pump operates in a discontinuous mode and requires a flying capacitor (C1) and a reservoir capacitor (C2) to generate the V- supply. RS-232-Compatible Driver The transmitter is an inverting level translator that converts CMOS-logic levels to EIA/TIA-232 compatible levels. It guarantees data rates up to 460kbps with worst-case loads of 3kΩ in parallel with 1000pF. When SHDN is driven low, the transmitter is disabled and put into tri-state. The transmitter input does not have an internal pullup resistor. increased without changing C1’s value. However, do not increase C1’s value without also increasing the value of C2 and CBYPASS to maintain the proper ratios (C1 to the other capacitors). When using the minimum 0.1µF capacitors, make sure the capacitance 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-. To reduce the output impedance at V-, use larger capacitors (up to 10µF). Bypass VCC to ground with at least 0.1µF. In applications sensitive to power-supply noise generated by the charge pump, decouple VCC to ground with a capacitor the same size as (or larger than) charge-pump capacitors C1 and C2. RS-232 Receiver The MAX3311E/MAX3313E receiver converts RS-232 signals to CMOS-logic output levels. The MAX3311E receiver will remain active during shutdown mode. The MAX3313E INVALID indicates when an RS-232 signal is present at the receiver input, and therefore when the port is in use. The MAX3313E INVALID output is pulled low when no valid RS-232 signal level is detected on the receiver input. MAX3311E Shutdown Mode In shutdown mode, the charge pump is turned off, V- is pulled to ground, and the transmitter output is disabled (Table 1). This reduces supply current typically to 1µA. The time required to exit shutdown is less than 25ms. Transmitter Output when Exiting Shutdown Figure 1 shows the transmitter output when exiting shutdown mode. The transmitter is loaded with 3kΩ in parallel with 1000pF. The transmitter output displays no ringing or undesirable transients as the MAX3311E comes out of shutdown. Note that the transmitter is enabled only when the magnitude of V- exceeds approximately -3V. High Data Rates The MAX3311E/MAX3313E maintain RS-232-compatible ±3.7V minimum transmitter output voltage even at Applications Information Capacitor Selection The capacitor type used for C1 and C2 is not critical for proper operation; either polarized or nonpolarized capacitors are acceptable. If polarized capacitors are used, connect polarity as shown in the Typical Operating Circuit. The charge pump requires 0.1µF capacitors. Increasing the capacitor values (e.g., by a factor of 2) reduces power consumption. C2 can be 5V/div 0 SHDN TIN = GND 1.5V/div 0 TOUT TIN = VCC Table 1. MAX3311E Shutdown Logic Truth Table 10µs/div SHDN TRANSMITTER OUTPUT RECEIVER OUTPUT CHARGE PUMP L High Z Active Inactive H Active Active Active Figure 1. Transmitter Output when Exiting Shutdown or Powering Up _______________________________________________________________________________________ 5 MAX3311E/MAX3313E Detailed Description MAX3311E/MAX3313E ±15kV ESD-Protected, 460kbps, 1µA, RS-232-Compatible Transceivers in µMAX high data rates. Figure 2 shows a transmitter loopback test circuit. Figure 3 shows the loopback test result at 120kbps, and Figure 4 shows the same test at 250kbps. ±15kV 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. The MAX3311E/MAX3313E driver outputs +5V and receiver inputs have extra protection against static discharge. Maxim’s engineers have developed state-ofthe-art structures to protect these pins against ESD of ±15kV 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 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 the product family are characterized for protection to ±15kV using the Human Body Model. 0.1µF ESD Test Conditions C1+ VCC VC2 C1 C1- MAX3311E MAX3313E Human Body Model Figure 5 shows the Human Body Model, and Figure 6 shows the current waveform it generates when discharged into 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. TOUT TIN ROUT RIN 5k 1000pF GND Figure 2. Loopback Test Circuit 5µs/div Figure 3. Loopback Test Results at 120kbps 6 ESD performance depends on a variety of conditions. Contact Maxim for a reliability report that documents test setup, test methodology, and test results. Machine Model The Machine Model for ESD tests all pins using a 200pF storage capacitor and zero discharge resistance. Its objective is to emulate the stress caused by contact that occurs with handling and assembly during manufacturing. Of course, all pins require this protection during manufacturing, not just RS-232 inputs and outputs. Therefore, after PC board assembly, the Machine Model is less relevant to I/O ports. TIN TIN TOUT TOUT ROUT ROUT 2µs/div Figure 4. Loopback Test Results at 250kbps _______________________________________________________________________________________ ±15kV ESD-Protected, 460kbps, 1µA, RS-232-Compatible Transceivers in µMAX CHARGE-CURRENT LIMIT RESISTOR HIGHVOLTAGE DC SOURCE Pin Configurations (continued) RD 1500Ω Cs 100pF DISCHARGE RESISTANCE DEVICE UNDER TEST STORAGE CAPACITOR Figure 5. Human Body ESD Test Model IP 100% 90% Ir VCC 1 C1- 2 INVALID 3 TIN ROUT 10 GND 9 C1+ 8 V- 4 7 TOUT 5 6 RIN MAX3313E µMAX PEAK-TO-PEAK RINGING (NOT DRAWN TO SCALE) AMPERES 36.8% 10% 0 0 tRL Chip Information TIME tDL CURRENT WAVEFORM TRANSISTOR COUNT: 278 Figure 6. Human Body Current Waveform INVALID HIGH RECEIVER INPUT LEVELS +2.7V INDETERMINATE +0.3V 0 INVALID LOW -0.3V INDETERMINATE -2.7V INVALID HIGH Figure 7. Receiver Positive/Negative Thresholds for INVALID _______________________________________________________________________________________ 7 MAX3311E/MAX3313E RC 1MΩ ______________________________________________________________Pin Description 10LUMAX.EPS MAX3311E/MAX3313E ±15kV ESD-Protected, 460kbps, 1µA, RS-232-Compatible Transceivers in µMAX 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. 8 _____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2001 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.