MAX3238 19-1144 Rev 1 10/02 +3.0V to +5.5V, 1A, up to 250kbps, True RS-232 Transceiver with AutoShutdown Plus General Description Features The MAX3238 true RS-232 transceiver achieves a 1A Supply Current Achieved with 1A supply current with Maxims revolutionary AutoShutdown Plus AutoShutdown Plus feature. When the device does Guaranteed Data Rate: 250kbps not sense a valid signal transition on either the receiver or transmitter inputs within 30sec, the on-board power 1A Low-Power Shutdown supply and drivers shut down. This occurs if the RS-232 Receivers Active in AutoShutdown Plus Mode cable is disconnected or if the transmitters of the con- nected peripheral are inactive. The system turns on Flow-Through Pinout again when a valid transition is applied to any RS-232 Meets EIA/TIA-232 Specifications Down to 3.0V receiver or transmitter input, saving power without changes to the existing BIOS or operating system. Guaranteed 6V/s Slew Rate The MAX3238 5-driver/3-receiver complete serial port is a 3V-powered EIA/TIA-232 and V.28/V.24 communica- tions interface intended for notebook or subnotebook computer applications. A proprietary, high-efficiency, Ordering Information dual charge-pump power supply and a low-dropout transmitter combine to deliver true RS-232 performance PART TEMP RANGE PIN-PACKAGE from a single +3.0V to +5.5V supply. A guaranteed MAX3238CAI 0C to +70C 28 SSOP data rate of 250kbps provides compatibility with popu- MAX3238EAI -40C to +85C 28 SSOP lar software for communicating with personal comput- ers. The MAX3238 requires only 0.1F capacitors in 3.3V operation. It is ideal for 3.3V-only systems, mixed 3.3V and 5.0V systems, or 5V-only systems that require true RS-232 performance. Receiver R1 has an extra, always-active output (in addi- tion to its standard output), which allows external Pin Configuration devices, such as a modem, to be monitored without for- ward biasing the protection diodes in circuitry that may have V completely removed. CC TOP VIEW The MAX3238 is available in a space-saving SSOP package. C2+ 1 28 C1+ V+ GND 2 27 Applications V C2- 3 26 CC Notebook, Subnotebook, and Palmtop C1- V- 4 25 Computers T1IN T1OUT 5 24 High-Speed Modems MAX3238 T2OUT 6 23 T2IN Battery-Powered Equipment T3OUT 22 7 T3IN Hand-Held Equipment R1IN 8 21 R1OUT Peripherals 20 R2IN 9 R2OUT Printers 10 19 T4IN T4OUT R3IN 11 18 R3OUT Typical Operating Circuit appears at end of data sheet. T5IN T5OUT 12 17 13 16 R1OUTB FORCEON 15 FORCEOFF 14 INVALID AutoShutdown Plus is a trademark of Maxim Integrated Products. SSOP *P Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com.+3.0V to +5.5V, 1A, up to 250kbps, True RS-232 Transceiver with AutoShutdown Plus ABSOLUTE MAXIMUM RATINGS V ...........................................................................-0.3V to +6V Short-Circuit Duration CC V+ (Note 1)...............................................................-0.3V to +7V T OUT (one at a time)............................................Continuous V- (Note 1) ................................................................+0.3V to -7V Continuous Power Dissipation (T = +70C) A V+ + V- (Note 1) .................................................................+13V SSOP (derate 9.52mW/C above +70C) ....................762mW Input Voltages Operating Temperature Ranges T IN, FORCEOFF, FORCEON..............................-0.3V to +6V MAX3238CAI ......................................................0C to +70C R IN .................................................................................25V MAX3238EAI....................................................-40C to +85C Output Voltages Storage Temperature Range ............................-65C to +160C T OUT...........................................................................13.2V Lead Temperature (soldering, 10s) ................................+300C R OUT, INVALID ....................................-0.3V to (V + 0.3V) CC Note 1: V+ and V- can have a maximum magnitude of +7V, but their absolute difference can not exceed +13V. 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 (V = +3.0V to +5.5V C1C4 = 0.1F (tested at 3.3V 5%), C1C4 = 0.22F (tested at 3.3V 10%), C1 = 0.047F and CC C2C4 = 0.33F (tested at 5.0V 10%) T = T to T unless otherwise noted. Typical values are at T = +25C.) A MIN MAX A PARAMETER CONDITIONS MIN TYP MAX UNITS DC CHARACTERISTICS V = 3.3V or 5.0V, T = +25C, receivers idle, CC A 1.0 10 Supply Current, AutoShutdown Plus transmitters idle, FORCEON = GND, A FORCEOFF = V CC 1.0 10 Supply Current, Shutdown FORCEOFF = GND, T = +25C A A Supply Current, AutoShutdown Plus FORCEON = FORCEOFF = V , no load 0.5 2.0 mA CC Disabled LOGIC INPUTS AND RECEIVER OUTPUTS Input Logic Threshold Low 0.8 V T IN, FORCEON, FORCEOFF V = 3.3V 2.0 CC Input Logic Threshold High V V = 5.0V 2.4 CC Input Leakage Current T IN, FORCEON, FORCEOFF 0.01 1.0 A Output Leakage Current Receivers disabled 0.05 10 A Output Voltage Low I = 1.6mA 0.4 V OUT V -V - CC CC Output Voltage High I = -1.0mA V OUT 0.6 0.1 RECEIVER INPUTS Input Voltage Range -25 25 V V = 3.3V 0.6 1.2 CC Input Threshold Low V V = 5.0V 0.8 1.5 CC V = 3.3V 1.5 2.4 CC Input Threshold High V V = 5.0V 1.8 2.4 CC Input Hysteresis 0.3 V Input Resistance T = +25C 35 7 k A 2 MAX3238