19-0198; Rev 0; 10/93 +3.3V-Powered, EIA/TIA-562 Dual Transceiver with Receivers Active in Shutdown The MAX563 is a +3.3V-powered EIA/TIA-562 transceiver with two transmitters and two receivers. Because it implements the EIA/TIA-562 standard, the MAX563 communicates with RS-232 transceivers, yet consumes far less power; this makes it ideal for battery-powered, hand-held computers. And, the MAX563 guarantees a 116kbps data rate while maintaining ±3.7V EIA/TIA-562 signal levels, which makes it compatible with LapLink™ software. An on-board charge pump converts the +3.3V supply to the ±6.6V needed to produce the EIA/TIA-562 output voltage levels. Four 0.1µF charge-pump capacitors and a bypass capacitor of similar size are the only external components required. When the MAX563’s charge pumps and transmitters are shut down to save power, the receivers remain active to continuously monitor signals from external devices (for example, ring indicator from modems). The two receivers’ outputs can be enabled and disabled independently of the shutdown function to allow two ports—generally of different types—to be wire-OR connected at the UART. ________________________Applications Handiterminals Battery-Powered Equipment Bar-Code Readers Notebook and Palmtop Computers ____________________________Features ♦ Guaranteed Interoperability with RS-232 ♦ Operates from a Single +3.0V to +3.6V Supply ♦ 2 Drivers, 2 Receivers ♦ Receivers Active in Shutdown Mode ♦ Low-Power Shutdown: 10µA Max ♦ Small Package—18-Pin Wide SO ♦ Three-State TTL/CMOS Receiver Outputs ♦ 116kbps Guaranteed Data Rate ______________Ordering Information PART TEMP. RANGE PIN-PACKAGE MAX563CPN 0°C to +70°C 18 Plastic DIP MAX563CWN MAX563C/D 0°C to +70°C 0°C to +70°C 18 Wide SO Dice * * Dice are specified at TA = +25°C. __________Typical Operating Circuit +3.3V C1 C2 V+ 4 C1- VOLTAGE DOUBLER 5 C2+ 6 400k V- 7 C4 400k VCC T2OUT 8 RS-562 OUTPUTS R1IN 14 5k 10 R2OUT R2IN 9 5k SHDN 18 RS-562/RS-232 INPUTS 18 SHDN C1+ 2 17 VCC V+ 3 16 GND C1- 4 T1OUT 15 11 T2IN 1 EN EN 1 VCC 13 R1OUT CMOS OUTPUTS TOP VIEW 3 -6.6V VOLTAGE INVERTER C2- 12 T1IN CMOS INPUTS ALL CAPACITORS 0.1µF +6.6V 17 VCC 2 C1+ __________________Pin Configuration C3 MAX563 15 T1OUT C2+ 5 14 R1IN C2- 6 13 R1OUT V- 7 12 T1IN T2OUT 8 11 T2IN R2IN 9 10 R2OUT DIP/SO ON/OFF GND ™ LapLink is a registered trademark of Traveling Software, Inc. ________________________________________________________________ Maxim Integrated Products Call toll free 1-800-998-8800 for free samples or literature. 1 MAX563 _______________General Description MAX563 +3.3V-Powered, EIA/TIA-562 Dual Transceiver with Receivers Active in Shutdown ABSOLUTE MAXIMUM RATINGS Power Supply Ranges Supply Voltage (VCC) ...........................................-0.3V to +6V Input Voltages TIN.........................................................-0.3V to (VCC -0.3V) RIN ...............................................................................±25V TOUT (Note 1)...................................................................±15V Output Voltages TOUT .............................................................................±15V ROUT ....................................................-0.3V to (VCC +0.3V) Driver/Receiver Output Short Circuit to GND.........Continuous Continuous Power Dissipation (TA = +70°C) Plastic DIP ....................................................................889mW Wide SO .......................................................................762mW Operating Temperature Range...............................0°C to +70°C Storage Temperature Range .............................-65°C to +160°C Lead Temperature (soldering, 10sec) .............................+300°C Note 1: Input voltage measured with TOUT in high-impedance state. SHDN or VCC = 0V. 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 3.6V, C1-C4 = 0.1µF, TA = TMIN to TMAX, unless otherwise noted.) PARAMETER SYMBOL CONDITIONS MIN TYP ±3.7 ±4.5 MAX UNITS RS-562 TRANSMITTERS Output Voltage Swing All transmitter outputs loaded with 3kΩ to GND Data Rate RL = 3kΩ, CL = 1000pF, TA = +25°C Input Logic Threshold Low VIL Input Logic Threshold High VIH 200 Output Leakage Current 116 kbps 0.6 V 2.4 SHDN = VCC Logic Pull-Up/Input Current V V 2 20 SHDN = 0V ±0.01 ±1 VCC = 3.6V, SHDN = 0V, VOUT = ±15V ±0.01 ±10 VCC = SHDN = 0V, VOUT = ±15V ±0.01 ±10 Transmitter Output Resistance VCC = V+ = V- = 0V, VOUT = ±2V Output Short-Circuit Current VOUT = 0V 300 µA Ω 10M ±15 µA ±60 mA ±25 V 0.4 V RS-232/RS-562 RECEIVERS Input Voltage Operating Range Input Threshold Low VIL VCC = 3.3V Input Threshold High VIH VCC = 3.3V 2.4 SHDN = VCC = 3.3V (no hysteresis when SHDN = 0V) 0.1 Input Hysteresis Input Resistance RIN Output Voltage Low VOL IOUT = 3.2mA Output Voltage High VOH IOUT = -0.5mA EN Input Threshold Low VIL EN Input Threshold High VIH 0.5 1.0 V 5 7 kΩ 0.2 0.4 V ±10 µA 0.6 V VCC-0.6 VCC-0.2 EN = VCC, 0V ≤ VOUT ≤ VCC Output Leakage Current 2 3 V ±0.05 2.4 _______________________________________________________________________________________ V V +3.3V-Powered, EIA/TIA-562 Dual Transceiver with Receivers Active in Shutdown (VCC = 3.0V to 3.6V, C1-C4 = 0.1µF, TA = TMIN to TMAX, unless otherwise noted.) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS 3.6 V POWER SUPPLY Operating Supply Voltage VCC VCC Supply Current ICC Shutdown Supply Current ICC 3.0 No load 3 RL = 3kΩ on both outputs, inputs static 8 Figure 1 TA = +25°C TA = TMIN to TMAX SHDN Input Leakage Current 0.1 10 2 50 0.1 SHDN Threshold Low VIL SHDN Threshold High VIH 8 mA µA ±1 µA 0.6 V 2.4 V AC CHARACTERISTICS CL = 50pF to 2500pF, RL = 3kΩ to 7kΩ, VCC = 3.3V, TA = +25°C, measured from +3V to -3V or -3V to +3V (Note 2) Transition Slew Rate Transmitter Propagation Delay tPHLT tPLHT Receiver Propagation Delay (Normal Operation) tPHLR Receiver Propagation Delay (Shutdown) tPHLS tPLHR tPLHS Figure 2 Figure 3 Figure 3 4 6 30 1.3 3.5 1.5 3.5 0.5 1.0 0.6 1.0 0.5 10.0 2.5 10.0 V/µs µs µs µs Receiver-Output Enable Time tER Figure 4 125 500 ns Receiver-Output Disable Time tDR Figure 4 160 500 ns Transmitter-Output Enable Time tET Includes charge pump start-up 300 µs Transmitter-Output Disable Time tDT Figure 5 600 ns Transmitter Propagation Delay Skew tPHLT – tPLHT 300 ns Receiver Propagation Delay Skew (Normal Operation) tPHLR – tPLHR 100 ns Note 2: Minimum slew rate is specified with CL = 1000pF for data rates above 20kbps, corresponding with EIA/TIA-562. __________________________________________________________________________ MAX563 ELECTRICAL CHARACTERISTICS (continued) MAX563 +3.3V-Powered, EIA/TIA-562 Dual Transceiver with Receivers Active in Shutdown ______________________________________________________________Pin Description PIN NAME FUNCTION 1 EN Receiver enable. Connect EN to GND to enable receivers, and take EN high to disable receivers. 2 C1+ 3 V+ +2VCC voltage generated by the positive charge pump. The voltage on V+ collapses to VCC when SHDN is low. 4 C1- Negative terminal of positive charge-pump capacitor. 5 C2+ Positive terminal of inverting charge-pump capacitor. 6 C2- Negative terminal of inverting charge-pump capacitor. 7 V- -2VCC voltage generated by the inverting charge pump. The voltage on V- collapses to GND when SHDN is low. 8, 15 T2OUT, T1OUT EIA/TIA-562 voltage-level transmitter outputs. These outputs are disabled (Hi-Z) when SHDN is low. 9, 14 R2IN, R1IN 10, 13 R2OUT, R1OUT 11, 12 T2IN, T1IN 16 GND Ground. 17 VCC +3.0V to +3.6V supply voltage. 18 SHDN Positive terminal of positive charge-pump capacitor. EIA/TIA-562 and EIA/TIA-232 voltage-level receiver inputs. CMOS receiver outputs. These outputs are active regardless of the state of SHDN. They are enabled when EN is low, and disabled (Hi-Z) when EN is high. CMOS driver inputs. Shutdown control. Connect to GND to shut down the charge pumps and the transmitters. Take high to turn on the charge pumps and to enable the transmitters. _______________Detailed Description The MAX563 consists of three sections: charge-pump voltage converters, transmitters (drivers), and receivers. Both the transmitters and the receivers are inverting. +3V to ±6V, Dual Charge-Pump Voltage Converter Two charge pumps either invert or double the incoming VCC to generate the voltages required by the transmitters. The first charge pump uses capacitor C1 to double VCC; the resulting voltage is stored on the V+ reservoir capacitor. The second charge pump uses capacitor C2 to invert V+; this negative voltage is stored on the V- capacitor. When SHDN is low, the charge pumps are turned off, V+ is pulled down to VCC by a 1kΩ resistor, and Vrises to GND. It is possible to draw some power from the V+ and Vpins for external use. However, doing so diminishes the charge-pump output voltages and reduces noise margins, so it is not recommended. 4 EIA/TIA-562 Transmitters The MAX563’s drivers are inverting level translators that convert +3V logic inputs to EIA/TIA-562 voltage levels. With a VCC supply of only 3.0V, the driver outputs deliver the EIA/TIA-562 ±3.7V minimum specification under worst-case conditions—when both transmitters are loaded with 3kΩ receivers (either EIA/TIA-232 or EIA/TIA-562). The transmitters are fast: the guaranteed data rate with standard loads is 116kbps, which is the highest rate commonly used by PC-to-PC communication software, such as LapLink. The highest practical data rate may be reduced if the other communicating device (RS-562 or RS-232) is not as fast, or if the cables present an excessive capacitive load (>1000pF). Each transmitter is designed to drive a single receiver; transmitters can be paralleled to drive multiple receivers. When SHDN is low, the driver outputs are turned off. Their output leakage currents are less than 10µA when pulled to GND or when driven to ±15V. This enables two transmitters to be connected to the same line, provided that one of them is always disabled by taking SHDN low. _______________________________________________________________________________________ +3.3V-Powered, EIA/TIA-562 Dual Transceiver with Receivers Active in Shutdown MAX563 0.1µF ISHDN +3.6V +3V INPUT 0.1µF OV C1+ 0.1µF 0.1µF VCC V+ MAX563 V- V+ OV C1C2+ V CC C2- OUTPUT V- 0.1µF tPLHT 400k tPHLT T1 & T2 +3.6V ROUT 0V +3.6V DRIVE TOUT TIN R1 & R2 Figure 2. Transmitter Propagation Delay Timing +3.6V EN SHDN 3k RIN 5k +3V GND 50% INPUT 50% 0V Figure 1. Shutdown Current Test Circuit The inputs of unused drivers may be left unconnected because they have internal 400kΩ pull-ups to V CC. Unused inputs may also be connected to GND or VCC, but VCC provides lower power consumption because of the internal pull-ups. VCC OUTPUT 50% tPHLR tPHLS 50% GND tPLHR tPLHS EIA/TIA-562 and EIA/TIA-232 Receivers The MAX563’s receivers convert ±3.7V to ±13.2V EIA/TIA-562 signal levels into +3V logic levels; they are rated to receive signals up to ±25V to accommodate EIA/TIA-232 signals as well. Both receivers invert. Their inputs are each equipped with an internal 5kΩ (nominal) terminating resistor connected to ground, and the input logic thresholds are 0.4V and 2.4V. The positive logic-low threshold (VIL) ensures the receiver outputs remain high whenever their inputs are left open. The receivers are active when EN is low, and have high-impedance outputs when EN is high. When SHDN is high, the receivers have hysteresis. This produces clean output transitions, even with slowmoving input signals that exhibit moderate amounts of noise and ringing. When shut down, the receivers have no hysteresis, and the propagation delay increases. Figure 3. Receiver Propagation Delay Timing and have hysteresis. When active in shutdown mode (EN = SHDN = low), the receivers operate at reduced power and speed, and without hysteresis. The charge pumps and transmitters operate only when SHDN is high; they are unaffected by EN. When shut down (SHDN = low) or unpowered (VCC = 0V), the transmitter outputs are high impedance if they are backdriven with voltages not exceeding ±15V. The pullup resistors at the driver inputs are disconnected in shutdown mode to save power. During shutdown, V+ is pulled down to VCC, and V- rises to GND. Shutdown and Enable Control The SHDN and EN controls are independent. Both receivers are always active when EN is low. With EN low and SHDN high, the receivers operate at full speed _______________________________________________________________________________________ 5 MAX563 +3.3V-Powered, EIA/TIA-562 Dual Transceiver with Receivers Active in Shutdown EN INPUT SHDN VCC +3V 0V 0V tER tDT VCC - 0.6V V+ RECEIVER OUTPUT CL = 150pF +3.7V +0.4V 0V VCC -3.7V EN INPUT RECEIVER OUTPUTS V- 0V tDR A. TIMING DIAGRAM VOH - 0.1V RL = 1kΩ VOL + 0.1V 0.5VCC 1 OR 0 TX 3k Figure 4. Receiver Output Enable and Disable Timing B. TEST CIRCUIT __________Applications Information Figure 5. Transmitter Output Disable Timing Charge-Pump Capacitor Selection Normally, 0.1µF capacitors can be used for all locations. To reduce output ripple, increase the values of the V+ and V- capacitors. If your capacitors have a very wide tolerance, consider using a nominal value a little larger than 0.1µF to ensure that the actual capacitance does not fall below about 80nF. For circuits designed to operate over a wide range of temperatures, consider using slightly larger capacitors to compensate for any loss of capacitance at temperature extremes. No advantage is gained by using values larger than 10µF. Power-Supply Decoupling Use a capacitor with the same value as the chargepump capacitors. 6 _______________________________________________________________________________________ 50pF +3.3V-Powered, EIA/TIA-562 Dual Transceiver with Receivers Active in Shutdown MAX563 Table 1. Summary of EIA/TIA-232E/V.28 and EIA/TIA-562 Specifications PARAMETER Driver Output Voltage 0 Level 1 Level CONDITION EIA/TIA-232E/V.28 SPECIFICATION EIA/TIA-562 SPECIFICATION 5.0V to 15.0V 3.7V to 13.2V -5.0V to -15.0V -3.7V to -13.2V No load ±25V ±13.2V CL = 2500pF Up to 20kbps Up to 20kbps CL = 1000pF Not defined Up to 64kbps 3.0V to 15.0V 3.0V to 15.0V -3.0V to -15.0V -3.0V to -15.0V ±25V ±25V Maximum Instantaneous Slew Rate 30V/µs 30V/µs Maximum Driver Output Short-Circuit Current 100mA 60mA 3kΩ to 7kΩ load Maximum Output Level Signal Rate (3kΩ ≤ RL ≤ 7kΩ) Receiver Input Thresholds 0 Level 1 Level Maximum Input Level V.28 1ms or 3% of the period Transition Rate on Driver Output Driver Output Resistance with Power Off RS-232 4% of the period -2V < VOUT < 2V 300Ω 4V/µs 300Ω Table 2. DB9/DB25 Cable Connections Commonly Used for EIA/TIA-232E, EIA/TIA-562 and V.24 Asynchronous Interfaces DB9 PIN DB25 PIN NAME SYMBOL 1 8 Received Line Signal Detector (sometimes called Data Carrier Detect) FUNCTION DCD Handshake from DCE 2 3 Receiver Data RxD Data from DCE 3 2 Transmit Data TxD Data from DTE 4 20 Data Terminal Ready DTR Handshake from DTE 5 7 Signal Ground GND Reference point for signals 6 6 Data Set Ready DSR Handshake from DCE 7 4 Request to Send RTS Handshake from DTE 8 5 Clear to Send CTS Handshake from DCE 9 22 Ring Indicator RI Handshake from DCE _______________________________________________________________________________________ 7 MAX563 +3.3V-Powered, EIA/TIA-562 Dual Transceiver with Receivers Active in Shutdown ___________________Chip Topography V+ C1+ EN SHDN GND V CC C1T1 OUT C2+ 0.105" (2.667 mm) C2VR1 IN R1 OUT T2 OUT T1 IN R2 IN R2 OUT T2 IN 0.070" (1.778 mm) TRANSISTOR COUNT: 189; SUBSTRATE CONNECTED TO V+. 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 © 1993 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.