19-0144; Rev. 0; 9/93 Complete 230kbps, 2.7V to 5.25V Serial Interface for Notebook Computers ________________________Applications Palmtop, Notebook, and Subnotebook Computers Peripherals Battery-Powered Equipment __________Typical Operating Circuit 0.33µF 0.33µF T1IN CMOS INPUTS T2IN T3IN R1OUT 12 13 6 18 T1 17 T2 16 T3 23 R1 T1OUT T2OUT EIA/TIA -562 OUTPUTS CMOS OUTPUTS R3OUT R4OUT R5OUT EN 7 22 R2 5k 8 9 R3 21 5k 20 R4 5k 10 14 19 R5 5k GND 27 ♦ Operates from a 2.7V to 5.25V Supply ♦ Designed for EIA/TIA-562 and EIA/TIA-232 Applications ♦ Guaranteed 4.0V/µs Slew Rate ♦ 3 Drivers, 5 Receivers ♦ Flow Through Pinout ♦ Low-Power Shutdown and Keep-Awake Modes ♦ Low-Cost, Surface-Mount External Capacitors ______________Ordering Information PART TEMP. RANGE MAX562CWI 0°C to +70°C MAX562CAI MAX562C/D MAX562EWI MAX562EAI 0°C to +70°C 0°C to +70°C -40°C to +85°C -40°C to +85°C PIN-PACKAGE 28 SO 28 SSOP Dice* 28 SO 28 SSOP * Contact factory for dice specifications. T3OUT 15 28 V+ V CC 1 C1A+ 2 27 GND C1B+ 3 26 V- C1B- 4 25 C2+ C1A- 5 MAX562 R2 OUT 7 R1IN R2IN R3IN TOP VIEW R1 OUT 6 5k R2OUT ♦ 230kbps Data Rate, LapLink™ Compatible __________________Pin Configuration MAX562 2 C1A 5 3 C1B 4 C1B+ C1B- 28 1 C1A+ C1AVOLTAGE VCC V+ 0.33µF C3 0.68µF DOUBLER/TRIPLER INPUT 25 C2+ VOLTAGE 26 C2 VINVERTER 24 C20.33µF C4 0.33µF +2.7V TO +5.25V 11 ____________________________Features EIA/TIA -562 INPUTS R4IN R5IN SHDN 24 C223 R1 IN 22 R2 IN R3 OUT 8 21 R3 IN R4 OUT 9 20 R4 IN R5 OUT 10 19 R5 IN T1 IN 11 18 T1 OUT T2 IN 12 17 T2 OUT T3 IN 13 16 T3 OUT EN 14 15 SHDN SO/SSOP ™ 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 MAX562 _______________General Description The MAX562 is designed specifically for notebook and palmtop computers that need to transfer data quickly. It runs at data rates up to 230kbps, and has a guaranteed 4V/µs slew rate. This device meets the new EIA/TIA-562 standard that guarantees compatibility with RS-232 interfaces. The MAX562 has low-power shutdown and keep-awake modes. In keep-awake mode, the transmitters are disabled but all receivers are active, allowing unidirectional communication. In shutdown mode, the entire chip is disabled and all outputs are in a high-impedance state. The MAX562 is available in a standard 28-pin SO package, and in a smaller footprint shrink small-outline package (SSOP). MAX562 Complete 230kbps, 2.7V to 5.25V Serial Interface for Notebook Computers ABSOLUTE MAXIMUM RATINGS VCC ......................................................................... -0.3V to +6V V+ ................................................................ (VCC - 0.3V) to +6V V- ............................................................................ +0.3V to -6V C1A+, C1B+.................................................. -6V to (V+ + 0.3V) C1A-, C1B-, C2+ ........................................ -0.3V to (V+ + 0.3V) C2- .................................................................. (V- - 0.3V) to +6V Input Voltages TIN, EN, SHDN ........................................ -0.3V to (VCC + 0.3V) RIN ....................................................................................±25V Output Voltages TOUT ............................................................................... ±15V ROUT ...................................................... -0.3V to (VCC + 0.3V) Short-Circuit Duration TOUT to GND ........................................................ Continuous ROUT to GND, VCC ................................................ Continuous Continuous Power Dissipation (TA = +70°C) SO (derate 12.50mW/°C above +70°C) .................. 1000mW SSOP (derate 9.52mW/°C above +70°C) ................. 762mW Operating Temperature Ranges: MAX562C_ _ ..................................................... 0°C to +70°C MAX562E_ _ .................................................. -40°C to +85°C Storage Temperature Range ........................... -65°C to +160°C Lead Temperature (soldering, 10sec) ........................... +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 = 2.7V to 5.25V, C1A = C1B = C2 = C4 = 0.33µF, C3 = 0.68µF, TA = TMIN to TMAX, unless otherwise noted.) PARAMETER CONDITIONS MIN TYP MAX UNITS ±3.7 ±4.5 ±6.0 V EIA/TIA-562 TRANSMITTERS Output Voltage Swing All transmitter outputs loaded with 3kΩ to GND Input Logic Threshold Low TIN, EN, SHDN Input Logic Threshold High TIN, EN, SHDN VCC = 2.7V to 3.6V 0.6 VCC = 5.0V +5%, -10% 0.8 VCC = 2.7V to 3.6V 1.8 VCC = 5.0V +5%, -10% 3.0 V Output Leakage Current Output Resistance VCC = V+ = V- = 0V, VOUT = ±2V Output Short-Circuit Current VOUT = 0V V ±10 µA ±60 mA ±25 V Ω 300 EIA/TIA-562 RECEIVERS Input Voltage Operating Range Input Threshold Low 0.8 V Input Threshold High Input Hysteresis No hysteresis when SHDN = 0V Input Resistance -15V < VIN < 15V Output Voltage Low IOUT = 1.6mA Output Voltage High IOUT = -1.0mA EN = GND, 0V ≤ ROUT ≤ VCC Output Leakage Current 2.4 V 7 kΩ 0.4 V ±10 µA 5.25 V 0.3 3 5 V VCC -0.5 V 0.05 POWER SUPPLY Operating Supply Voltage 2.7 No load 20 All outputs loaded 3kΩ 24 33 VCC Power-Supply Current VCC = 3.3V Shutdown Supply Current with Receivers Active EN = VCC, SHDN = GND, TA = +25°C 45 130 µA Shutdown Supply Current SHDN = EN = GND, TA = +25°C 1 50 µA 2 _______________________________________________________________________________________ mA Complete 230kbps, 2.7V to 5.25V Serial Interface for Notebook Computers PARAMETER Data Rate Transmitter Slew Rate Transmitter Rise/Fall Time Transmitter Propagation Delay CONDITIONS 1000pF || 3kΩ load each transmitter output, 150pF load each receiver output CL = 50pF to 2500pF, RL = 3kΩ to 7kΩ. Measured from +3V to -3V, or -3V to +3V MIN TYP 230.4 280.0 4 6 MAX kbits/sec 30 RL = 3kΩ measured from +3.3V to -3.3V or -3.3V to +3.3V CL = 2500pF 0.22 3.1 CL = 1000pF 0.22 2.1 2500pF || 3kΩ load, Figure 1 tPHLT 900 1700 tPLHT 1000 1700 Transmitter-Output Enable Time UNITS V/µs µs ns tET 100 Figure 3 tDT 600 CL = 150pF, SHDN = VCC Figure 2 tPHLR 100 250 tPLHR 250 500 tPHLS 3000 4000 tPLHS 2000 3000 Receiver-Output Enable Time CL = 150pF, SHDN = GND Figure 2 Figure 4 tER 100 250 ns Receiver-Output Disable Time Figure 4 tDR 250 500 ns Transmitter-Output Disable Time Receiver Propagation Delay, Normal Operation Receiver Propagation Delay, Keep-Awake Mode µs ns ns ns _______________________________________________________________________________________ 3 MAX562 AC CHARACTERISTICS __________________________________________Typical Operating Characteristics (VCC = 3.3V, C1A = C1B = C2 = C4 = 0.33µF, C3 = 0.68µF, TA=+25°C, unless otherwise noted.) TRANSMITTER OUTPUT VOLTAGE vs. TEMPERATURE TRANSMITTER OUTPUT VOLTAGE (V-, V+) ALL OUTPUTS LOADED 3kΩ II CL 7.5 6.5 SLEW+ 6.0 5.5 5.0 SLEW- 4.5 4.0 0 1000 2000 3000 4000 5000 T_OUT+ ..... +3.7V EIA/TIA-562 ALL TRANSMITTERS LOADED 3kΩ ..... -3.7V EIA/TIA-562 T_OUT-40 0 40 80 SUPPLY CURRENT vs. SUPPLY VOLTAGE SUPPLY CURRENT (mA) 32 30 28 26 1000 30 24 20 22 4.5 5.0 5.5 ALL TRANSMITTERS LOADED 3kΩ 28 22 2000 VCC = +3.3V 45 2 OUTPUTS LOADED 3kΩ II 2500pF 30 25 -40 0 40 80 1 OUTPUT LOADED 3kΩ II 2500pF 0 50 100 SUPPLY CURRENT vs. TEMPERATURE SHDN = 0, EN = 1 ALL TRANSMITTERS LOADED 3kΩ 55 50 VCC = +3.3V 45 VCC = +2.7V 40 -40 0 40 150 DATA RATE (kbps) TEMPERATURE (°C) SUPPLY CURRENT (µA) 5000 35 60 80 TEMPERATURE (°C) 4 4000 3 OUTPUTS LOADED 3kΩ II 2500pF 40 20 VCC (V) 35 3000 50 VCC = +2.7V 32 24 4.0 0 55 34 26 3.5 T_OUT- SUPPLY CURRENT vs. TRANSMITTER DATA RATE 36 34 3.0 ALL TRANSMITTERS LOADED 3kΩ II CL CL (pF) 38 ALL TRANSMITTERS LOADED 3kΩ 2.5 T_OUT+ SUPPLY CURRENT vs. TEMPERATURE 38 36 6 5 4 3 2 1 0 -1 -2 -3 -4 -5 -6 TEMPERATURE (°C) CL(pF) SUPPLY CURRENT (mA) SLEW RATE (V/µs) 7.0 6 5 4 3 2 1 0 -1 -2 -3 -4 -5 -6 TRANSMITTER OUTPUT VOLTAGE vs. LOAD CAPACITANCE, TO 231kbps TRANSMITTER OUTPUT VOLTAGE (V-, V+) TRANSMITTER SLEW RATE vs. LOAD CAPACITANCE 8.0 SUPPLY CURRENT (mA) MAX562 Complete 230kbps, 2.7V to 5.25V Serial Interface for Notebook Computers _______________________________________________________________________________________ 200 250 Complete 230kbps, 2.7V to 5.25V Serial Interface for Notebook Computers PIN NAME FUNCTION 28 V+ 2, 5 C1A+, C1A- Terminals for positive charge-pump capacitor 3, 4 C1B+, C1B- Terminals for positive charge-pump capacitor 6, 7, 8, 9, 10 R_OUT 11, 12, 13 T_IN TTL/CMOS Driver Inputs 14 EN Receiver Enable, see Shutdown and Enable Control section. 15 SHDN Shutdown Control, see Shutdown and Enable Control section. 16, 17, 18 T_OUT EIA/TIA-562 Driver Outputs 19, 20, 21, 22, 23 R_IN EIA/TIA-562 Receiver Inputs 24, 25 C2+, C2- Terminals for negative charge-pump capacitor 26 V- Negative charge-pump output, typically -5.2V 27 GND Ground 1 VCC +2.7V to +5.25V Supply Voltage Positive charge-pump output, typically 5.8V TTL/CMOS Receiver Outputs. +3V INPUT +3V 0V INPUT VOH 0V VOL OUTPUT tPLHT tPHLT Figure 1. Transmitter Propagation Delay Timing OUTPUT 50% 50% 0V VCC 50% tPHLR tPHLS 50% GND tPLHR tPLHS Figure 2. Receiver Propagation Delay Timing _______________________________________________________________________________________ 5 MAX562 ______________________________________________________________Pin Description MAX562 Complete 230kbps, 2.7V to 5.25V Serial Interface for Notebook Computers EN R_OUT SHDN +3V 1k VOH -1V, VOL +1.6V R_ R_IN A. TEST CIRCUIT 0V 150pF OUTPUT DISABLE TIME (tDT) VOH EN INPUT +3V 0V +3V TRANSMITTER OUTPUTS EN OUTPUT ENABLE TIME (tER) 0V VOH -3V RECEIVER OUTPUTS VOL VOL B. ENABLE TIMING A. TIMING DIAGRAM +3V 1 OR 0 EN INPUT TX EN 0V OUTPUT DISABLE TIME (tDR) 3k 50pF B. TEST CIRCUIT VOH VOH -0.5V RECEIVER OUTPUTS VOL +0.5V VOL C. DISABLE TIMING Figure 3. Transmitter-Output Disable Timing _______________Detailed Description The MAX562 has three sections: the charge-pump voltage converter, the drivers (transmitters), and the receivers. Charge-Pump Voltage Converter The charge-pump voltage converter is used to produce a positive and a negative supply to drive the transmitters. The positive voltage (V+) is generated by a regulated charge pump working as either a doubler or a tripler (depending on the VCC level) and using capacitors C1A, C1B and C3 (see Typical Operating Circuit). The negative voltage (V-) derives from V+ using a simple charge-pump inverter that employs capacitors C2 and C4. These charge-pump converters are regulated to give output voltages of +5.8V and -5.2V. Having regulated supplies generated on-chip makes the MAX562's performance insensitive to variations in VCC from 2.7V to 5.25V, transmitter loading changes, and operating temperature changes. When SHDN is low, the charge pumps are disabled, V+ is internally connected to VCC, and V- is internally connected to GND. 6 Figure 4. Receiver-Output Enable and Disable Timing EIA/TIA-562 Drivers The driver output voltage is guaranteed to meet the ±3.7V EIA/TIA-562 specification over the full range of operating temperatures and voltages, when each transmitter is loaded with up to 3kΩ and operated up to 230kbps (see Typical Operating Characteristics). The typical driver output voltage swing exceeds ±4V with a 3kΩ load on all transmitter outputs. The open-circuit output voltage swing is typically from (V+ - 0.7V) to (V- + 0.7V). Output swing is not significantly dependent on VCC since the charge pumps are regulated. Input thresholds are CMOS and TTL compatible. Connect unused inputs to VCC or to GND. When SHDN is low, the driver outputs are off and their leakage currents are less than 10µA, even if the transmitter outputs are back-driven between -7V and +15V. Taking SHDN low does not disable the receivers. When SHDN and EN are both low, the entire chip is disabled and all outputs are high impedance. Power consumption is lowest in this condition. Exiting shutdown takes about 100µs, but depends on VCC. Figure 5 shows _______________________________________________________________________________________ Complete 230kbps, 2.7V to 5.25V Serial Interface for Notebook Computers SHDN 0 6 VOLTS (V) 4 2 VCC = +2.2V V CC = +2.7V V CC = +3.3V V CC = +5.0V 0 -2 -4 0 100 200 300 TIME (µs) Figure 5. Time for Transmitters to Exit Shutdown The guaranteed 0.8V and 2.4V receiver input thresholds are significantly tighter than the ±3.0V thresholds required by the EIA/TIA-562 specification. This allows the receiver inputs to respond to TTL/CMOS logic levels as well as EIA/TIA-562/232 levels. Also, the MAX562's guaranteed 0.8V lower threshold ensures that receivers shorted to ground will have a logic 1 output. The 5kΩ input resistance to ground ensures that a receiver with its input left open will also have a logic 1 output. The receiver inputs have approximately 0.3V hysteresis when SHDN is high. This provides clean output transitions, even with slowly moving input signals with moderate noise and ringing. The receivers are active when EN is high. When EN is low, the receiver outputs are high impedance. This allows wire-OR connection of two EIA/TIA-562 ports (or ports of different types) at the UART. the MAX562 transmitter outputs when SHDN rises. Two transmitter outputs are shown going to opposite EIA/TIA562 levels (one transmitter input is high, the other is low). Each transmitter is loaded with 3kΩ in parallel with 2500pF. The transmitter outputs are well behaved, with no ringing or undesirable transients as they come out of shutdown. The receivers are always active,when EN is high, irrespective of SHDN's state. When SHDN is high, the receivers have hysteresis and experience the shortest propagation delays (typically 100ns falling, 250ns rising). When SHDN is low, the receivers have longer propagation delays (typically 3µs falling, 2µs rising) and have no hysteresis. The receiver outputs are not valid for 50µs after SHDN goes low. Driving Multiple Receivers Each transmitter is designed to drive a single receiver. Transmitters can be paralleled to drive multiple receivers. SHDN and EN determine the operation of the MAX562 as shown in Table 1. EIA/TIA-562 Receivers All 5 receivers are identical and accept EIA/TIA-562 or EIA/TIA-232 signals. The CMOS receiver outputs swing between VCC and GND. They are inverting, maintaining compatibility with the driver outputs. Shutdown and Enable Control __________Applications Information Capacitor Selection The capacitor type is not critical for proper MAX562 operation. Any low cost ceramic capacitor (e.g., Z5U, Y5V) is acceptable for operating at room temperature, Table 1. MAX562 Control Pin Configurations SHDN EN CHARGE-PUMP OPERATION STATUS TRANSMITTERS T1-T3 0 0 Shutdown High-Z High-Z 1µ 0 1 Shutdown High-Z Active* 45µ 1 0 Normal Operation Active High-Z 24m 1 1 Normal Operation Active Active 24m RECEIVERS R1-R5 SUPPLY CURRENT TYP (A) * Active, but with reduced performance (see EIA/TIA-562 Receivers section). This is “keep-awake” mode. _______________________________________________________________________________________ 7 MAX562 5 MAX562 Complete 230kbps, 2.7V to 5.25V Serial Interface for Notebook Computers Table 2. Summary of EIA/TIA-232E/V.28 and EIA/TIA-562 Specifications PARAMETER CONDITION Driver Output Voltage 0 Level 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 3kΩ to 7kΩ load 1 Level Maximum Output Level No load Signal Rate (3kΩ ≤ RL ≤ 7kΩ) ±25V ±13.2V CL = 2500pF Up to 20kbps Up to 20kbps CL = 1000pF Not defined Up to 64kbps and X7R ceramic capacitors are recommended for operation over the full temperature range. ___________________Chip Topography Larger capacitors may be used for C2 and C4 (see Typical Operating Circuit) to reduce ripple on the transmitter output voltages. C1B+ C1A+ 3 2 V CC 1 V+ GND V- 28 27 26 C2+ 25 Power-Supply Decoupling In applications that are sensitive to power-supply noise, decouple V CC to ground with a capacitor similar in value to that of the C1A and C1B charge-pump capacitors. Connect the bypass capacitor as close as possible to the VCC and GND pins. 24 C1BC1A- 4 0.164" (4.166mm) 5 V+ and V- as Power Supplies A small amount of power can be drawn from V+ and V-. Excessive loads will cause V+ and V- to fall out of regulation. When V+ or V- are loaded, check for good regulation over the intended operating temperature range. 23 R1 OUT R2 OUT R3 OUT R4 OUT R5 OUT C2- 6 R1 IN 22 R2 IN 21 R3 IN 7 8 20 R4 IN 19 R5 IN 9 10 11 12 13 14 15 16 17 18 T2 IN EN T3 OUT T1 OUT T1 IN T3 IN SHDN T2 OUT 0.135" (3.429mm) Substrate connected to V+ Transistor count: 1892 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.