LTC1383 5V Low Power RS232 Transceiver U FEATURES ■ ■ ■ ■ ■ ■ ■ ■ ■ DESCRIPTIO The LTC®1383 is an ultra-low power 2-driver/2-receiver RS232 transceiver that operates from a single 5V supply. The charge pump requires only four spacesaving 0.1µF capacitors. The supply current (ICC) of the transceiver is only 220µA with driver outputs unloaded. Operates from a Single 5V Supply Low Supply Current: ICC = 220µA ESD Protection Over ±10kV Available in 16-Pin SOIC Narrow Package Uses Small Capacitors: 0.1µF Operates to 120kBaud Output Overvoltage Does Not Force Current Back into Supplies RS232 I/O Lines Can Be Forced to ±25V Without Damage Pin Compatible with LT1181A and MAX232A The LTC1383 is fully compliant with all data rate and overvoltage RS232 specifications. The transceiver can operate up to 120kbaud with a 2500pF, 3kΩ load. Both driver outputs and receiver inputs can be forced to ±25V without damage and can survive multiple ±10kV ESD strikes. U APPLICATIO S ■ Notebook Computers Palmtop Computers , LTC and LT are registered trademarks of Linear Technology Corporation. U ■ TYPICAL APPLICATIO Quiescent Supply Current vs Temperature 16 3 2 4 0.1µF LOGIC INPUT 5 LTC1383 600 500 0.1µF 6 0.1µF VCC 300k 11 14 232 OUTPUT VCC 300k LOGIC INPUT LOGIC OUTPUT LOGIC OUTPUT 10 7 12 13 5k 8 9 5k TEST CONDITION: VCC = 5V VCC = 5V 232 OUTPUT 232 INPUT 232 INPUT QUIESCENT CURRENT (µA) 0.1µF 1 400 QUIESCENT CURRENT 300 200 100 0 –20 0 20 40 TEMPERATURE (°C) 60 80 LTC1383 • TA02 15 LTC1383 • TA01 1383fa 1 LTC1383 W W W AXI U U ABSOLUTE RATI GS Supply Voltage (VCC) ................................................ 6V Input Voltage Driver ....................................... – 0.3V to V CC + 0.3V Receiver ............................................... – 25V to 25V Digital Input ............................... – 0.3V to VCC + 0.3V Output Voltage Driver .................................................... – 25V to 25V Receiver .................................... – 0.3V to VCC + 0.3V Short-Circuit Duration V + ................................................................... 30 sec V – ................................................................... 30 sec Driver Output .............................................. Indefinite Receiver Output .......................................... Indefinite Operating Temperature Range LTC1383C ............................................... 0°C to 70°C LTC1383I ............................................ – 40°C to 85°C Storage Temperature Range ................ – 65°C to 150°C Lead Temperature (Soldering, 10 sec)................. 300°C U U W PACKAGE/ORDER I FOR ATIO ORDER PART NUMBER TOP VIEW C1+ 1 16 VCC V+ 2 15 GND C1– 3 14 TR1 OUT C2+ 4 13 RX1 IN C2 – 5 12 RX1 OUT V– 6 11 TR1 IN TR2 OUT 7 10 TR2 IN RX2 IN 8 9 N PACKAGE 16-LEAD PDIP LTC1383CN LTC1383CS LTC1383IN LTC1383IS RX2 OUT S PACKAGE 16-LEAD PLASTIC SO TJMAX = 125°C, θJA = 70°C/W (N) TJMAX = 125°C, θJA = 90°C/W (S) Consult LTC Marketing for parts specified with wider operating temperature ranges. DC ELECTRICAL CHARACTERISTICS The ● denotes specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VCC = 5V, C1 = C2 = C3 = C4 = 0.1µF, unless noted. PARAMETER CONDITIONS Any Driver Output Voltage Swing 3k to GND Logic Input Voltage Level Logic Input Current Output Short-Circuit Current Any Receiver Input Voltage Thresholds Hysteresis Input Resistance Output Voltage Output Short-Circuit Current Power Supply Generator V + Output Voltage V – Output Voltage MIN TYP ● ● 5.0 – 5.0 Input Low Level (VOUT = High) Input High Level (VOUT = Low) VIN = VCC VIN = 0V VOUT = 0V ● ● 2.0 7.0 – 6.5 1.4 1.4 ±9 – 20 ±12 Input Low Threshold Input High Threshold ● ● 0.8 ● 0.1 3 – 10V ≤ VIN ≤ 10V Output Low, IOUT = – 1.6mA (VCC = 5V) Output High, IOUT = 160µA (VCC = 5V) Sinking Current, VOUT = VCC Sourcing Current VOUT = 0V IOUT = 0mA IOUT = 8mA IOUT = 0mA IOUT = – 8mA Positive Negative ● ● ● ● 3.0 – 15 10 1.3 1.7 0.4 5 0.2 3.2 – 40 20 8.0 7.5 – 8.0 – 7.0 MAX 0.8 5 – 40 2.4 1 7 0.4 UNITS V V V V µA µA mA V V V kΩ V V mA mA V V V V 1383fa 2 LTC1383 DC ELECTRICAL CHARACTERISTICS The ● denotes specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VCC = 5V, C1 = C2 = C3 = C4 = 0.1µF, unless noted. PARAMETER Power Supply VCC Supply Current CONDITIONS No Load (Note 2), 0°C to 70°C No Load (Note 2), – 40°C to 85°C MIN TYP MAX UNITS 0.5 1.0 0.8 2.0 0.22 0.35 1.4 1.4 mA mA V V ● ● Digital Input Threshold Low Digital Input Threshold High ● ● AC CHARACTERISTICS The ● denotes specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VCC = 5V, C1 = C2 = C3 = C4 = 0.1µF, unless noted. PARAMETER Slew Rate CONDITIONS RL = 3k, CL = 51pF RL = 3k, CL = 2500pF t HLD (Figure 1) t LHD (Figure 1) t HLR (Figure 2) t LHR (Figure 2) Driver Propagation Delay (TTL to RS232) Receiver Propagation Delay (RS232 to TTL) MIN 3 ● ● ● ● Note 1: Absolute Maximum Ratings are those values beyond which the life of the device may be impaired. TYP 8 5 2 2 0.3 0.3 MAX 30 UNITS V/µs V/µs µs µs µs µs 3.5 3.5 0.8 0.8 Note 2: Supply current is measured with driver and receiver outputs unloaded. U W TYPICAL PERFOR A CE CHARACTERISTICS Driver Output Voltage vs Temperature DRIVER OUTPUT VOLTAGE (V) 6 OUTPUT HIGH VCC = 5V 2.0 VCC = 4.5V 4 2 0 –2 OUTPUT LOW VCC = 4.5V –4 –6 VTH 1.8 1.6 VTL 1.4 –8 20 30 40 50 TEMPERATURE (°C) 30 25 20 15 10 5 1.0 10 35 1.2 VCC = 5V 0 VCC = 5V RL = 3k CL = 2500pF 2 DRIVERS ACTIVE 40 SUPPLY CURRENT (mA) RL = 3k 8 Supply Current vs Data Rate 45 2.2 THRESHOLD VOLTAGE (V) 10 Receiver Input Thresholds vs Temperature 60 70 LTC1383 • TPC01 0 10 40 30 50 20 TEMPERATURE (˚C) 60 70 LTC1383 • TPC02 0 0 25 50 75 100 125 DATA RATE (kBAUD) 150 175 LTC1383 • TPC03 1383fa 3 LTC1383 U W TYPICAL PERFOR A CE CHARACTERISTICS VCC Supply Current vs Temperature Driver Output Waveforms Receiver Output Waveforms 18 DRIVER OUTPUT RL = 3k CL = 2500pF SUPPLY CURRENT (mA) 16 14 12 DRIVER OUTPUT RL = 3k 2 DRIVERS LOADED RL = 3k 10 RECEIVER OUTPUT CL = 51pF INPUT 8 1 DRIVER LOADED RL = 3k 6 INPUT 4 LTC1383 • TPC05 2 5µs/DIV LTC1383 • TPC06 5µs/DIV 0 0 10 20 30 40 50 TEMPERATURE (°C) 60 70 LTC1383 • TPC04 U U U PI FU CTIO S VCC: 5V Input Supply Pin. This pin should be decoupled with a 0.1µF ceramic capacitor. charge pump efficiency, the capacitor’s effective series resistance should be less than 2Ω. GND: Ground Pin. TR IN: RS232 Driver Input Pins. Inputs are TTL/CMOS compatible. The inputs of unused drivers can be left unconnected since 300k input pull-up resistors to VCC are included on chip. V +: Positive Supply Output (RS232 Drivers). V + ≅ 2V CC – 2V. This pin requires an external capacitor C = 0.1µF for charge storage. The capacitor may be tied to ground or VCC. With multiple devices, the V + and V – pins may share a common capacitor. For large numbers of devices, increasing the size of the shared common storage capacitors is recommended to reduce ripple. TR OUT: Driver Outputs at RS232 Voltage Levels. The driver outputs are protected against ESD to ±10kV for human body model discharges. V –: Negative Supply Output (RS232 Drivers). V – ≅ – (2VCC – 2V). This pin requires an external capacitor C = 0.1µF for charge storage. RX IN: Receiver Inputs. These pins can be forced to ±25V without damage. The receiver inputs are protected against ESD to ±10kV for human body model discharges. Each receiver provides 0.4V of hysteresis for noise immunity. C1+, C1–, C2+, C2–: Commutating Capacitor Inputs. These pins require two external capacitors C = 0.1µF: one from C1+ to C1– and another from C2+ to C2 –. To maintain RX OUT: Receiver Outputs with TTL/CMOS Voltage Levels. 1383fa 4 LTC1383 U W W SWITCHI G TI E WAVEFOR S DRIVER INPUT VCC 1.4V 1.4V 0V V+ DRIVER OUTPUT 0V 0V t LHD RX OUTPUT V– VCC 1.7V RX INPUT 1.3V 2.4V 0.8V t LHR t HLD 0V t HLR VCC 0V LTC1383 • F02 LTC1383 • F01 Figure 1. Driver Propagation Delay Timing Figure 2. Receiver Propagation Delay Timing TEST CIRCUITS Receiver Timing Test Load Driver Timing Test Load DRIVER INPUT DRIVER OUTPUT RX OUTPUT RX INPUT DRIVER 51pF RX 51pF 3k LTC1383 • TA04 LTC1383 • TA03 ESD Test Circuit 0.1µF 1 16 3 2 4 0.1µF LOGIC INPUT 5 LTC1383 VCC 0.1µF 6 0.1µF VCC 300k 11 14 232 OUTPUT VCC 300k LOGIC INPUT LOGIC OUTPUT LOGIC OUTPUT 10 7 12 13 5k 8 9 5k 232 OUTPUT 232 INPUT RS232 LINE PINS PROTECTED TO ±10kV 232 INPUT 15 LTC1383 • TA05 1383fa 5 LTC1383 U TYPICAL APPLICATIO S Paralleling Power Supply Generator with Common Storage Capacitors 0.1µF 1 16 3 2 4 0.1µF LOGIC INPUT 5 LTC1383 VCC = 5V 0.1µF 6 0.1µF VCC 300k 14 11 0.1µF 232 OUTPUT 1 16 3 2 4 0.1µF LOGIC INPUT 5 LOGIC OUTPUT LOGIC OUTPUT 6 VCC 300k 14 11 VCC 300k LOGIC INPUT LTC1383 VCC = 5V 232 OUTPUT VCC 300k 10 7 12 13 5k 8 9 5k 15 232 OUTPUT LOGIC INPUT 232 INPUT LOGIC OUTPUT 232 INPUT LOGIC OUTPUT 10 7 12 13 5k 8 9 5k 232 OUTPUT 232 INPUT 232 INPUT 15 LTC1383 • TA06 1383fa 6 LTC1383 U PACKAGE DESCRIPTIO N Package 16-Lead PDIP (Narrow .300 Inch) (Reference LTC DWG # 05-08-1510) .770* (19.558) MAX 16 15 14 13 12 11 10 9 1 2 3 4 5 6 7 8 .255 ± .015* (6.477 ± 0.381) .300 – .325 (7.620 – 8.255) .008 – .015 (0.203 – 0.381) ( +.035 .325 –.015 +0.889 8.255 –0.381 ) .130 ± .005 (3.302 ± 0.127) .045 – .065 (1.143 – 1.651) .020 (0.508) MIN .065 (1.651) TYP .120 (3.048) MIN .100 (2.54) BSC NOTE: 1. DIMENSIONS ARE INCHES MILLIMETERS *THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .010 INCH (0.254mm) .018 ± .003 (0.457 ± 0.076) N16 1002 1383fa Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights. 7 LTC1383 U PACKAGE DESCRIPTIO S Package 16-Lead Plastic Small Outline (Narrow .150 Inch) (Reference LTC DWG # 05-08-1610) .386 – .394 (9.804 – 10.008) NOTE 3 .045 ±.005 .050 BSC 16 N 15 14 13 12 11 10 9 N .245 MIN .160 ±.005 .150 – .157 (3.810 – 3.988) NOTE 3 .228 – .244 (5.791 – 6.197) 1 .030 ±.005 TYP 2 3 N/2 N/2 RECOMMENDED SOLDER PAD LAYOUT 1 .010 – .020 × 45° (0.254 – 0.508) .008 – .010 (0.203 – 0.254) 2 3 4 5 6 7 8 .053 – .069 (1.346 – 1.752) .004 – .010 (0.101 – 0.254) 0° – 8° TYP .016 – .050 (0.406 – 1.270) NOTE: 1. DIMENSIONS IN .050 (1.270) BSC .014 – .019 (0.355 – 0.483) TYP S16 0502 INCHES (MILLIMETERS) 2. DRAWING NOT TO SCALE 3. THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .006" (0.15mm) RELATED PARTS PART NUMBER DESCRIPTION COMMENTS LT1780/LT1781 5V, 2 Driver, 2 Receiver RS232 Transeivers ±15kV ESD per IEC 1000-4 LTC1382 5V, 2 Driver, 2 Receiver RS232 Transceiver 220µA Supply Current, 0.2µA in Shutdown LTC1384 5V, 2 Driver, 2 Receiver RS232 Transceiver 220µA Supply Current, 2 Receivers Active in Shutdown LTC1385 3.3V, 2 Driver, 2 Receiver RS562 Transceiver 220µA Supply Current, 2 Receivers Active in Shutdown LTC1386 3.3V, 2 Driver, 2 Receiver RS562 Transceiver 220µA Supply Current, Narrow 16-pin SO 1383fa 8 Linear Technology Corporation LW/TP 1002 1K REV A • PRINTED IN USA 1630 McCarthy Blvd., Milpitas, CA 95035-7487 (408) 432-1900 ● FAX: (408) 434-0507 ● linear.com LINEAR TECHNOLOGY CORPORATION 1994