EVALUATION KIT AVAILABLE Click here for production status of specific part numbers. 1A Supply Current, 1.8V to 4.25V-Powered MAX3218 RS-232 Transceiver with AutoShutdown General Description Features The MAX3218 RS-232 transceiver is intended for bat- BETTER THAN BIPOLAR tery-powered EIA/TIA-232E and V.28/V.24 communica- 1A Supply Current Using AutoShutdown tions interfaces that need two drivers and two receivers Operates Directly from Two Alkaline, with minimum power consumption from a single low- voltage supply. It provides a wide +1.8V to +4.25V NiCd or NiMH Cells operating voltage range while maintaining true RS-232 +1.8V to +4.25V Single-Supply Voltage Range and EIA/TIA-562 voltage levels. The MAX3218 runs 120kbps Data Rate Guaranteed from two alkaline, NiCd, or NiMH cells without any form of voltage regulator. A guaranteed 120kbps data rate Low-Cost Surface-Mount Components provides compatibility with popular software for com- Meets EIA/TIA-232E Specifications municating with personal computers. Three-State Receiver Outputs Supply current is reduced to 1A with Maxims new AutoShutdown feature. When the MAX3218 does not Flow-Through Pinout sense a valid signal level on the receiver inputs, the on- On-Board DC-DC Converters board power-supply and drivers shut down. This occurs if the RS-232 cable is disconnected or if the 20-Pin SSOP and DIP Packages transmitters of the connected peripheral are turned off. The system turns on again when a valid level is applied to either RS-232 receiver input. As a result, the system Ordering Information saves power without changes to the existing software. PART TEMP RANGE PIN-PACKAGE Additionally, the MAX3218 can be forced into or out of shutdown, under logic control. MAX3218CPP+ 0C to +70C 20 Plastic DIP While shut down, all receivers can remain active or can MAX3218CAP+ 0C to +70C 20 SSOP be disabled under logic control, permitting a system MAX3218EAP+ -40C to +85C 20 SSOP incorporating the CMOS MAX3218 to monitor external devices while in low-power shutdown. Three-state dri- +Denotes a lead(Pb)-free/RoHS-compliant package. vers are provided on both receiver outputs so that multi- ple receivers, generally of different interface standards, can be on the same bus. The MAX3218 is available in Pin Configuration 20-pin DIP and SSOP packages. TOP VIEW + Applications LX GND 1 20 Battery-Powered Equipment INVALID V+ 2 19 Subnotebook Computers C1+ FORCEON 3 18 PDAs FORCEOFF 4 17 GND Hand-Held Equipment GND 5 C1- 16 MAX3218 Peripherals V CC 6 15 V- Cellular Phones T1IN 7 14 T1OUT T2IN 8 13 T2OUT R1OUT R1IN 9 12 R2OUT 10 11 R2IN DIP/SSOP AutoShutdown is a trademark of Maxim Integrated Products. 19-0380 Rev 2 5/181A Supply Current, 1.8V to 4.25V-Powered MAX3218 RS-232 Transceiver with AutoShutdown Absolute Maximum Ratings Supply Voltages Short-Circuit Duration, R OUT, T OUT to GND ....... Continuous V ....................................................................-0.3V to +4.6V Continuous Power Dissipation (T = +70C) CC A V+.......................................................... (V - 0.3V) to +7.5V Plastic DIP (derate 11.11mW/C above +70C) ..........889mW CC V- .......................................................................+0.3V to -7.4V SSOP (derate 8.00mW/C above +70C) ..................640mW V to V-..........................................................................+12V Operating Temperature Ranges CC LX ................................................................-0.3V to (1V + V+) MAX3218C P................................................... 0C to +70C Input Voltages MAX3218E P ................................................. -40C to +85C T IN, FORCEON, FORCEOFF ............................ -0.3V to +7V Storage Temperature Range ........................... -65C to +150C R IN .................................................................................25V Lead Temperature (soldering, 10sec) ........................... +300C Output Voltages T OUT.............................................................................15V) R OUT....................................................-0.3V to (V + 0.3V) CC 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 (Circuit of Figure 1, V = 1.8V to 4.25V, C1 = 0.47F, C2 = C3 = C4 = 1F, L1 = 15H, T = T to T , unless otherwise noted. CC A MIN MAX Typical values are at V = 3.0V, T = +25C.) CC A PARAMETER CONDITIONS MIN TYP MAX UNITS DC CHARACTERISTICS Operating Voltage Range 1.8 4.25 V V = 3.0V, T = +25C, all R IN open, CC A Supply Current, AutoShutdown 1.0 10 A FORCEON = GND, FORCEOFF = V CC Supply Current, Shutdown FORCEOFF = GND, T = +25C, V = 3.0V 1.0 10 A A CC Supply Current, FORCEON = FORCEOFF = V = 3.0V, no load 2.0 3.0 mA CC AutoShutdown Disabled LOGIC INPUTS AND RECEIVER OUTPUTS Input Logic Threshold Low T IN, FORCEON, FORCEOFF 0.33 x V V CC Input Logic Threshold High T IN, FORCEON, FORCEOFF 0.67 x V V CC Input Leakage Current T IN, FORCEON = FORCEOFF = 0V or V 0.001 1 A CC Output Voltage Low R OUT, I = 1.0mA 0.4 V OUT Output Voltage High R OUT, I = -0.4mA V - 0.25 V - 0.08 V OUT CC CC R OUT, 0V R OUT V , CC Output Leakage Current 0.05 10 A FORCEON = FORCEOFF = 0V AUTOSHUTDOWN (FORCEON = GND, FORCEOFF = V ) CC Positive threshold 2.8 Receiver Input Thresholds, Figure 4a V Transmitters Enabled Negative threshold -2.8 Receiver Input Thresholds 1A supply current, Figure 4a -0.3 0.3 V Transmitters Disabled INVALID Output Low Voltage I = 1.0mA, -0.3V < R IN < 0.3V 0.4 V OUT INVALID Output High Voltage V - 0.25 V I = -0.4mA, R IN > 2.8V CC OUT www.maximintegrated.com Maxim Integrated 2