LTC1347

LTC1347 5V Low Power RS232 3-Driver/5-Receiver Transceiver with 5 Receivers Active in Shutdown FEATURES ■ ■ ■ ■ ■ ■ ■ ■ DESCRIPTIO ■ ■ ■ Low Supply Current: 300µA Five Receivers Kept Alive in Shutdown ESD Protection Over ±10kV Operates from a Single 5V Supply Uses Small Capacitors: 0.1µF Operates to 120kBaud Three-State Outputs Are High Impedance When Off Output Overvoltage Does Not Force Current Back into Supplies RS232 I/O Lines Can Be Forced to ± 25V Without Damage Pin Compatible with LT1137A and LT1237 Flowthrough Architecture The LTC®1347 is a 3-driver/5-receiver RS232 transceiver with very low supply current. In the no load condition, the supply current is only 300µA. The charge pump only requires four 0.1µF capacitors. In Shutdown mode, all five receivers are kept alive and the supply current is 80µA. All RS232 outputs assume a high impedance state in Shutdown and with the power off. The LTC1347 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. APPLICATIO S ■ ■ Notebook Computers Palmtop Computers , LTC and LT are registered trademarks of Linear Technology Corporation. TYPICAL APPLICATIO V+ C1 0.1µF C2 0.1µF DRIVER 1 OUT RX1 IN DRIVER 2 OUT RX2 IN RX3 IN RX4 IN DRIVER 3 OUT RX5 IN ON/OFF NC VCC 3-Drivers/5-Receivers with Shutdown 1 2 3 4 5 6 7 8 9 10 11 12 13 14 LTC1347 28 27 26 25 24 23 22 21 20 19 18 17 16 15 C3 0.1µF DRIVER 1 IN RX1 OUT DRIVER 2 IN RX2 OUT RX3 OUT RX4 OUT DRIVER 3 IN RX5 OUT GND NC NC 1347 TA01 Quiescent and Shutdown Supply Current vs Temperature 1200 120 100 SHUTDOWN CURRENT (µA) SHUTDOWN CURRENT 80 60 QUIESCENT CURRENT 40 20 V– C4 0.1µF 1000 QUIESCENT CURRENT (µA) 800 600 400 200 0 –40 0 0 80 100 20 60 40 TEMPERATURE (°C) TEST CONDITION: VCC = 5V, ALL DRIVER INPUTS TIED TO VCC. –20 1347 TA02 U 1347fa U U 1 LTC1347 ABSOLUTE AXI U RATI GS PACKAGE/ORDER I FOR ATIO TOP VIEW V+ 1 28 V– 27 C2+ 26 C2– 25 DR1 IN 24 RX1 OUT 23 DR2 IN 22 RX2 OUT 21 RX3 OUT 20 RX4 OUT 19 DR3 IN 18 RX5 OUT 17 GND 16 NC 15 NC NW PACKAGE 28-LEAD PDIP VCC 2 C1+ 3 C1– 4 DR1 OUT 5 RX1 IN 6 DR2 OUT 7 RX2 IN 8 RX3 IN 9 RX4 IN 10 DR3 OUT 11 RX5 IN 12 ON/OFF 13 NC 14 G PACKAGE 28-LEAD SSOP Supply Voltage (VCC) ................................................ 6V Input Voltage Driver ....................................... – 0.3V to V CC + 0.3V Receiver ............................................... – 25V to 25V On/Off Pin .................................. – 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 .................... 0°C to 70°C Storage Temperature Range ................ – 65°C to 150°C Lead Temperature (Soldering, 10 sec)................. 300°C ORDER PART NUMBER LTC1347CG LTC1347CNW LTC1347CSW SW PACKAGE 28-LEAD PLASTIC SO TJMAX = 125°C, θJA = 96°C/W (G) TJMAX = 125°C, θJA = 56°C/W (NW) TJMAX = 125°C, θJA = 85°C/W (SW) Consult LTC Marketing for parts specified with wider operating temperature ranges. DC ELECTRICAL CHARACTERISTICS PARAMETER Any Driver Output Voltage Swing Logic Input Voltage Level Logic Input Current Output Short-Circuit Current Output Leakage Current Any Receiver Input Voltage Thresholds Hysteresis Input Resistance Output Voltage Output Short-Circuit Current CONDITIONS 3k to GND The ● denotes specifications which apply over the full operating temperature range. VCC = 5V, C1 = C2 = C3 = C4 = 0.1µF, unless otherwise noted. MIN Positive Negative ● ● ● ● ● ● TYP 7.0 – 6.5 1.4 1.4 MAX UNITS V V V V µA µA mA 5.0 – 5.0 2.0 Input Low Level (VOUT = High) Input High Level (VOUT = Low) VIN = 5V VIN = 0V VOUT = 0V Shutdown, VOUT = ±20V (Note 3) Input Low Threshold Input High Threshold VIN = ± 10V Output Low, IOUT = – 1.6mA (VCC = 5V) Output High, IOUT = 160µA (VCC = 5V) Sinking Current, VOUT = VCC Sourcing Current, VOUT = 0V 0.8 5 –5 ±9 ± 10 ● ● ● ● ● ±12 ± 500 1.3 1.7 0.4 5 0.2 4.8 – 40 20 µA V V V kΩ V V mA mA 0.8 0.1 3 3.5 – 15 10 2.4 1.0 7 0.4 1347fa 2 U W U U WW W LTC1347 DC ELECTRICAL CHARACTERISTICS PARAMETER Power Supply Generator V + Output Voltage V – Output Voltage Supply Rise Time Power Supply VCC Supply Current CONDITIONS IOUT = 0mA IOUT = 12mA IOUT = 0mA IOUT = – 12mA Shutdown to Turn-On The ● denotes specifications which apply over the full operating temperature range. VCC = 5V, C1 = C2 = C3 = C4 = 0.1µF, unless otherwise noted. MIN TYP 8.0 7.5 – 8.0 – 7.0 0.2 MAX UNITS V V V V ms No Load (All Drivers VIN = 5V)(Note 2) No Load (All Drivers VIN = 0V) (Note 2) Shutdown (Note 3) ● ● ● ● ● On/Off Threshold Low On/Off Threshold High 2.0 0.6 0.8 80.0 1.4 1.4 1.1 1.3 120.0 0.8 mA mA µA V V AC CHARACTERISTICS PARAMETER Slew Rate Driver Propagation Delay (TTL to RS232) Receiver Propagation Delay (RS232 to TTL) The ● denotes specifications which apply over the full operating temperature range. VCC = 5V, C1 = C2 = C3 = C4 = 0.1µF, unless otherwise noted. 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) MIN 3 ● ● ● ● TYP 8 5 2 2 0.3 0.2 MAX 30 3.5 3.5 0.8 0.8 UNITS V/µs V/µs µs µs µs µs Note 1: Absolute Maximum Ratings are those values beyond which the life of the device may be impaired. Note 2: Supply current is measured with driver and receiver outputs unloaded. Note 3: Supply current and leakage current measurements in Shutdown are performed with VON/OFF = 0V. TYPICAL PERFOR A CE CHARACTERISTICS Driver Output Voltage 10 8 RL = 3k OUTPUT HIGH VCC = 5V DRIVER OUTPUT VOLTAGE (V) THRESHOLD VOLTAGE (V) SUPPLY CURRENT (mA) 6 4 2 0 –2 –4 –6 VCC = 4.5V OUTPUT LOW VCC = 4.5V VCC = 5V –8 –40 –20 20 0 40 60 TEMPERATURE (°C) UW 80 1347 G01 Receiver Input Thresholds 2.2 2.0 1.8 VTH 1.6 VTL 1.4 1.2 1.0 –40 –20 Supply Current vs Data Rate 45 40 35 30 25 20 15 10 5 0 VCC = 5V RL = 3k CL = 2500pF 3 DRIVERS ACTIVE 100 40 20 60 0 TEMPERATURE (˚C) 80 100 0 25 75 100 125 50 DATA RATE (kBAUD) 150 175 1347 G02 1347 G03 1347fa 3 LTC1347 TYPICAL PERFOR A CE CHARACTERISTICS VCC Supply Current 20 16 3 DRIVERS LOADED RL = 3k LEAKAGE CURRENT (µA) SUPPLY CURRENT (mA) 14 12 10 8 6 4 2 0 0 10 30 20 40 50 TEMPERATURE (°C) 60 70 1 DRIVER LOADED RL = 3k 35 30 25 20 15 10 5 0 0 10 30 20 40 50 TEMPERATURE (°C) 60 70 VOUT = 20V VOUT = – 20V SHORT-CIRCUIT CURRENT (mA) Receiver Short-Circuit Current 60 SHORT-CIRCUIT CURRENT (mA) 50 40 ISC– 30 ISC+ 20 1347 G08 1347 G09 10 –40 –20 40 20 0 60 TEMPERATURE (°C) PI FU CTIO S VCC: 5V Input Supply Pin. Supply current is typically 80µA in the Shutdown mode. This pin should be decoupled with a 0.1µF ceramic capacitor. GND: Ground Pin. ON/OFF: TTL/CMOS Compatible Shutdown Pin. A logic low puts the device in the Shutdown mode with all receivers kept alive, and the supply current is 80µA. All driver outputs are in high impedance state. This pin cannot float. V + : P ositive Supply Output (RS232 Drivers). V + ≅ 2VCC – 1V. 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 be paralleled into common capacitors. For large numbers of devices, increasing the size of the shared common storage capacitors is recommended to reduce ripple. V – : N egative Supply Output (RS232 Drivers). V – ≅ – (2VCC – 1.5V). This pin requires an external capacitor C = 0.1µF for charge storage. 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 1347fa 4 UW 1347 G04 Driver Leakage in Shutdown 45 40 20 18 16 14 12 10 8 6 4 Driver Short-Circuit Current ISC– ISC+ 0 –40 –20 20 0 40 60 TEMPERATURE (°C) 80 100 1347 G05 1347 G06 Driver Output Waveforms DRIVER OUTPUT RL = 3k CL = 2500pF DRIVER OUTPUT RL = 3k INPUT Receiver Output Waveforms RECEIVER OUTPUT CL = 51pF INPUT 80 100 1347 G07 U U U LTC1347 PI FU CTIO S charge pump efficiency, the capacitor’s effective series resistance should be less than 2Ω. DRIVER IN: RS232 Driver Input Pins. Inputs are TTL/ CMOS compatible. Inputs should not be allowed to float. Tie unused inputs to VCC. DRIVER OUT: Driver Outputs at RS232 Voltage Levels. Outputs are in a high impedance state when in Shutdown mode or VCC = 0V. The driver outputs are protected against ESD to ±10kV for human body model discharges. 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. RX OUT: Receiver Outputs with TTL/CMOS Voltage Levels. All receivers are kept alive in Shutdown. SWITCHI G TI E WAVEFOR S DRIVER INPUT DRIVER OUTPUT t LHD VCC 1.4V 1.4V 0V V+ 0V t HLD 1347 F01 Figure 1. Driver Propagation Delay Timing RX INPUT RX OUTPUT t LHR 1.7V Figure 2. Receiver Propagation Delay Timing W W U U U U 0V V– VCC 1.3V 0V 2.4V 0.8V t HLR VCC 0V 1347 F02 1347fa 5 LTC1347 TEST CIRCUITS DRIVER INPUT DRIVER OUTPUT DRIVER 51pF 3k RX INPUT RX RX OUTPUT 51pF 1347 F03 1347 F04 Figure 3. Driver Timing Test Load Figure 4. Receiver Timing Test Load V+ C1 0.1µF C2 0.1µF DRIVER 1 OUT RX1 IN RS232 LINE PINS PROTECTED TO ±10kV DRIVER 2 OUT RX2 IN RX3 IN RX4 IN DRIVER 3 OUT RX5 IN ON/OFF NC VCC 1 2 3 4 5 6 7 8 9 10 11 12 13 14 LTC1347 28 27 26 25 24 23 22 21 20 19 18 17 16 15 V– C3 0.1µF DRIVER 1 IN RX1 OUT DRIVER 2 IN RX2 OUT RX3 OUT RX4 OUT DRIVER 3 IN RX5 OUT GND NC NC 1347 TC01 C4 0.1µF Figure 5. ESD Test Circuit 1347fa 6 LTC1347 PACKAGE DESCRIPTIO U G Package 28-Lead Plastic SSOP (5.3mm) (Reference LTC DWG # 05-08-1640) 9.90 – 10.50* (.390 – .413) 28 27 26 25 24 23 22 21 20 19 18 17 16 15 1.25 ± 0.12 5.3 – 5.7 7.40 – 8.20 (.291 – .323) 0.65 BSC 1 2 3 4 5 6 7 8 9 10 11 12 13 14 2.0 (.079) 0° – 8° 7.8 – 8.2 0.42 ± 0.03 RECOMMENDED SOLDER PAD LAYOUT 5.00 – 5.60** (.197 – .221) 0.09 – 0.25 (.0035 – .010) 0.55 – 0.95 (.022 – .037) 0.65 (.0256) BSC NOTE: 1. CONTROLLING DIMENSION: MILLIMETERS MILLIMETERS 2. DIMENSIONS ARE IN (INCHES) 3. DRAWING NOT TO SCALE *DIMENSIONS DO NOT INCLUDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED .152mm (.006") PER SIDE **DIMENSIONS DO NOT INCLUDE INTERLEAD FLASH. INTERLEAD FLASH SHALL NOT EXCEED .254mm (.010") PER SIDE 0.22 – 0.38 (.009 – .015) 0.05 (.002) G28 SSOP 0802 NW Package 28-Lead PDIP (Wide .600 Inch) (Reference LTC DWG # 05-08-1520) 1.455* (36.957) MAX 28 27 26 25 24 23 22 21 20 19 18 17 16 15 .505 – .560* (12.827 – 14.224) 1 .600 – .625 (15.240 – 15.875) .150 ± .005 (3.810 ± 0.127) .015 (0.381) MIN 2 3 4 5 6 7 8 9 10 11 12 13 14 .045 – .065 (1.143 – 1.651) .009 – .015 (0.229 – 0.381) +.035 .625 –.015 .070 (1.778) TYP .125 (3.175) MIN .035 – .080 (0.889 – 2.032) .100 (2.54) BSC .018 ± .003 (0.457 ± 0.076) INCHES MILLIMETERS *THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .010 INCH (0.254mm) NOTE: 1. DIMENSIONS ARE ( 15.87 +0.889 –0.381 ) NW28 0502 1347fa 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 LTC1347 PACKAGE DESCRIPTIO U SW Package 28-Lead Plastic Small Outline (Wide .300 Inch) (Reference LTC DWG # 05-08-1620) .030 ±.005 TYP N 28 27 26 25 24 .050 BSC .045 ±.005 .697 – .712 (17.70 – 18.08) NOTE 4 23 22 21 20 19 18 17 16 15 N .420 MIN .325 ±.005 NOTE 3 .394 – .419 (10.007 – 10.643) N/2 RECOMMENDED SOLDER PAD LAYOUT .291 – .299 (7.391 – 7.595) NOTE 4 .010 – .029 × 45° (0.254 – 0.737) 0° – 8° TYP 1 2 3 N/2 1 .093 – .104 (2.362 – 2.642) 2 3 4 5 6 7 8 9 10 11 12 13 14 .037 – .045 (0.940 – 1.143) .005 (0.127) RAD MIN .009 – .013 (0.229 – 0.330) NOTE 3 .016 – .050 (0.406 – 1.270) .050 (1.270) BSC NOTE: 1. DIMENSIONS IN .014 – .019 (0.356 – 0.482) TYP .004 – .012 (0.102 – 0.305) INCHES (MILLIMETERS) 2. DRAWING NOT TO SCALE 3. PIN 1 IDENT, NOTCH ON TOP AND CAVITIES ON THE BOTTOM OF PACKAGES ARE THE MANUFACTURING OPTIONS. THE PART MAY BE SUPPLIED WITH OR WITHOUT ANY OF THE OPTIONS 4. THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .006" (0.15mm) S28 (WIDE) 0502 RELATED PARTS PART NUMBER LT1137A LTC1327 LTC1337 LTC1348 DESCRIPTION 5V, 3 Driver, 5 Receiver RS232 Transceiver 3.3V, 3 Driver, 5 Receiver RS562 Transceiver 5V, 3 Driver, 5 Receiver RS232 Transceiver 3.3V to 5V, 3 Driver, 5 Receiver RS232 Transceiver COMMENTS ± 15kV ESD per IEC 1000-4 300µA Supply Current, 0.2µA in Shutdown 300µA Supply Current, 1µA in Shutdown True RS232 on 3.3V, 5 Receivers Active in Shutdown 1347fa 8 Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7487 (408) 432-1900 ● FAX: (408) 434-0507 ● LW/TP 1002 1K REV A • PRINTED IN USA WWW.linear.com  LINEAR TECHNOLOGY CORPORATION 1994