MAX3311CUB

19-1901; Rev 0; 2/01 460kbps, 1µA Supply Current, RS-232-Compatible Transceivers in µMAX Features ♦ 1µA Low-Power Shutdown (MAX3311) ♦ INVALID Output (MAX3313) ♦ Receiver Active in Shutdown (MAX3311) ♦ Single Transceiver (1Tx/1Rx) in 10-Pin µMAX ♦ RS-232-Compatible Operation The MAX3311 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 MAX3313 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. Ordering Information ________________________Applications PART TEMP. RANGE PIN-PACKAGE Digital Cameras MAX3311CUB 0°C to +70°C 10 µMAX PDAs MAX3311EUB -40°C to +85°C 10 µMAX MAX3313CUB 0°C to +70°C 10 µMAX MAX3313EUB -40°C to +85°C 10 µMAX GPS POS Telecommunications Typical Operating Circuit Handy Terminals Set-Top Boxes +5V Pin Configurations CBYPASS 0.1µF C1 0.1µF TOP VIEW 1 9 2 C1+ VCC C1- 8 C2 0.1µF C1- MAX3311 MAX3313 4 TIN VCC 1 V- TOUT 7 10 GND 2 MAX3311 9 C1+ 8 V- 5 ROUT SHDN 3 TIN 4 7 TOUT ROUT 5 6 RIN µMAX Pin Configurations continued at end of data sheet. RIN 6 5kΩ SHDN (MAX3311) 3 INVALID (MAX3313) GND 10 CAPACITORS MAY BE POLARIZED OR NONPOLARIZED. ________________________________________________________________ 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. MAX3311/MAX3313 General Description The MAX3311/MAX3313 are low-power, +5V EIA/TIA232-compatible transceivers. Both devices have one transmitter and one receiver. The transceivers have a proprietary low-dropout transmitter output stage enabling RS-232-compatible operation from a +5V supply with a single inverting charge pump. These devices require only three 0.1µF capacitors and will run at data rates up to 460kbps while maintaining RS-232-compatible output levels. MAX3311/MAX3313 460kbps, 1µA Supply Current, 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_CUB .......................................................0°C to +70°C MAX331_EUB ....................................................-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 (MAX3311 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 Output Voltage High VOL VOH IOUT = 1.6mA IOUT = -1.0mA VCC 0.6 VCC 0.1 V INVALID OUTPUT (MAX3313 ONLY) Figure 5, positive threshold Receiver Input Threshold to INVALID Output High Receiver Input Threshold to INVALID Output Low 2.7 Figure 5, negative threshold -2.7 Figure 5 -0.3 INVALID Output Low VOL IOUT = 1.6mA INVALID Output High VOH IOUT = -1.0mA VCC - 0.6 V 0.3 V 0.4 V V Receiver Positive or Negative Threshold to INVALID High Figure 5 0.1 µs Receiver Positive or Negative Threshold to INVALID Low Figure 5 30 µs 2 _________________________________________________________________________________________ 460kbps, 1µA Supply Current, 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 ground ±3.7 Output Resistance (Note 1) VCC = 0, transmitter output = ±2V 300 V Ω Output Short-Circuit Current VOUT = ±12V, transmitter disabled Output Leakage Current ±60 mA ±25 µA MAX UNITS 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 Receiver Propagation Delay CONDITIONS RL = 3kΩ, CL = 1000pF tPLH, tPHL Receiver input to receiver output CL = 150pF MIN TYP 460 kbps 0.15 µs Transmitter Skew 100 ns Receiver Skew 50 ns 11 V/µs Transition Region Slew Rate RL = 3kΩ to 7kΩ, CL = 150pF to 1000pF, measured from +3V to -3V or from -3V to +3V _______________________________________________________________________________________ 3 MAX3311/MAX3313 ELECTRICAL CHARACTERISTICS (continued) Typical Operating Characteristics (VCC = +5V, 0.1µF capacitors, transmitter loaded with 3kΩ and CL, TA = +25°C, unless otherwise noted.) +SLEW 10 8 -SLEW 6 4 2 5 4 3 460kbps/250kbps/120kbps 2 1 0 -1 -2 460kbps/250kbps/120kbps -3 -5 0 500 1000 1500 2000 2500 3000 460kbps 12 250kbps 10 120kbps 8 20kbps 6 4 2 -4 0 14 SUPPLY CURRENT (mA) 12 6 SUPPLY CURRENT vs. LOAD CAPACITANCE MAX3311/13 toc02 250 kbps DATA RATE TRANSMITTER OUTPUT VOLTAGE (V) MAX3311/13 toc01 14 TRANSMITTER OUTPUT VOLTAGE vs. LOAD CAPACITANCE 0 0 500 1000 1500 2000 2500 3000 0 LOAD CAPACITANCE (pF) LOAD CAPACITANCE (pF) MAX3311/13 toc03 SLEW RATE vs. LOAD CAPACITANCE SLEW RATE (V/µs) MAX3311/MAX3313 460kbps, 1µA Supply Current, RS-232-Compatible Transceivers in µMAX 500 1000 1500 2000 2500 3000 LOAD CAPACITANCE (pF) Pin Description PIN 4 NAME FUNCTION MAX3311 MAX3313 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. RS-232 Receiver Input RS-232-Compatible Transmitter Output -4.3V generated by the charge pump. Connect a 0.1µF capacitor to ground. _______________________________________________________________________________________ 460kbps, 1µA Supply Current, RS-232-Compatible Transceivers in µMAX Single Charge-Pump Voltage Converter The MAX3311/MAX3313 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 three state. The transmitter input does not have an internal pullup resistor. RS-232 Receiver The MAX3311/MAX3313 receiver converts RS-232 signals to CMOS-logic output levels. The MAX3311 receiver will remain active during shutdown mode. The MAX3313 INVALID indicates when an RS-232 signal is present at the receiver input, and therefore when the port is in use. The MAX3313 INVALID output is pulled low when no valid RS-232 signal level is detected on the receiver input. factor of 2) reduces power consumption. C2 can be 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. 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 MAX3311 comes out of shutdown. Note that the transmitter is enabled only when the magnitude of V- exceeds approximately -3V. MAX3311 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 typically less than 100µs. Applications Information 5V/div 0 SHDN TIN = GND 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 1.5V/div 0 TOUT TIN = VCC Table 1. MAX3311 Shutdown Logic Truth Table SHDN TRANSMITTER OUTPUT RECEIVER OUTPUT CHARGE PUMP L High Z Active Inactive H Active Active Active 10µs/div Figure 1. Transmitter Output when Exiting Shutdown or Powering Up _______________________________________________________________________________________ 5 MAX3311/MAX3313 Detailed Description +5V 0.1µF C1+ VCC VTIN C2 C1 C1- MAX3311 MAX3313 TIN ROUT TOUT TOUT RIN ROUT 5kΩ 1000pF 5µs/div GND Figure 3. Loopback Test Results at 120kbps Figure 2. Loopback Test Circuit INVALID HIGH TIN +2.7V TOUT ROUT RECEIVER INPUT LEVELS MAX3311/MAX3313 460kbps, 1µA Supply Current, RS-232-Compatible Transceivers in µMAX INDETERMINATE +0.3V 0 INVALID LOW -0.3V INDETERMINATE -2.7V INVALID HIGH 2µs/div Figure 4. Loopback Test Results at 250kbps Figure 5. Receiver Positive/Negative Thresholds for INVALID High Data Rates The MAX3311/MAX3313 maintain RS-232-compatible transmitter output voltage (±3.7V minimum) even at 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. 6 _______________________________________________________________________ 460kbps, 1µA Supply Current, RS-232-Compatible Transceivers in µMAX Pin Configurations (continued) TRANSISTOR COUNT: 278 VCC 1 C1- 2 INVALID 3 TIN 4 ROUT 5 10 GND MAX3313 9 C1+ 8 V- 7 TOUT 6 RIN µMAX 10LUMAX.EPS Package Information 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 _____________________ 7 © 2001 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products. MAX3311/MAX3313 Chip Information