LTC1349 5V Low Power RS232 3-Driver/5-Receiver Transceiver with 2 Receivers Active in Shutdown U FEATURES ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ DESCRIPTIO Low Supply Current: 300µA Two Receivers Kept Alive in Shutdown ESD Protection Over ±10kV Operates from a Single 5V Supply Uses Small Capacitors: 0.1µF Operates to 120k Baud 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 U APPLICATIO S ■ ■ Notebook Computers Palmtop Computers The LTC®1349 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, two receivers are kept alive and the supply current is 35µA. All RS232 outputs assume a high impedance state in Shutdown and with the power off. The LTC1349 is fully compliant with all data rate and overvoltage RS232 specifications. The transceiver can operate up to 120k baud 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. , LTC and LT are registered trademarks of Linear Technology Corporation. U TYPICAL APPLICATIO Quiescent and Shutdown Supply Current vs Temperature 3-Drivers/5-Receivers with Shutdown VCC DRIVER 1 OUT RX1 IN DRIVER 2 OUT RX2 IN RX3 IN RX4 IN DRIVER 3 OUT RX5 IN ON/OFF NC 2 28 LTC1349 V– 27 3 26 4 25 5 24 6 23 7 22 8 21 9 20 10 19 11 18 12 17 13 16 14 15 C3 0.1µF C4 0.1µF 1200 60 1000 50 DRIVER 1 IN RX1 OUT DRIVER 2 IN RX2 OUT RX3 OUT RX4 OUT SHUTDOWN CURRENT 800 40 30 600 QUIESCENT CURRENT 400 20 SHUTDOWN CURRENT (µA) C2 0.1µF 1 QUIESCENT CURRENT (µA) V+ C1 0.1µF 10 200 DRIVER 3 IN RX5 OUT 0 0 80 100 20 60 40 TEMPERATURE (°C) TEST CONDITION: VCC = 5V, ALL DRIVER INPUTS TIED TO VCC. 0 –40 GND NC NC LTC1349 • TA01 –20 LTC1349 • TA02 1349fa 1 LTC1349 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 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 Commercial (LTC1349C) ........................ 0°C to 70°C Industrial (LTC1349I) ........................ – 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 TOP VIEW V+ 1 28 V– VCC 2 27 C2+ C1+ 3 26 C2– C1– 4 25 DR1 IN DR1 OUT 5 ORDER PART NUMBER LTC1349CG LTC1349CNW LTC1349CSW LTC1349IG LTC1349INW LTC1349ISW 24 RX1 OUT RX1 IN 6 23 DR2 IN DR2 OUT 7 22 RX2 OUT RX2 IN 8 21 RX3 OUT RX3 IN 9 20 RX4 OUT RX4 IN 10 19 DR3 IN DR3 OUT 11 18 RX5 OUT RX5 IN 12 17 GND ON/OFF 13 16 NC NC 14 15 NC NW PACKAGE 28-LEAD PDIP G PACKAGE 28-LEAD SSOP 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 The ● denotes specifications which apply over the full operating temperature range. VCC = 5V, C1 = C2 = C3 = C4 = 0.1µF, unless noted. PARAMETER Any Driver Output Voltage Swing CONDITIONS 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 Output Leakage Current Power Supply Generator V + Output Voltage V – Output Voltage Supply Rise Time MIN TYP ● ● 5.0 – 5.0 Input Low Level (VOUT = High) Input High Level (VOUT = Low) VIN = 5V VIN = 0V VOUT = 0V ● ● 2.0 7.0 – 6.5 1.4 1.4 Shutdown, VOUT = ±20V (Note 3) ● Input Low Threshold Input High Threshold ● ● 0.8 ● 0.1 3 3k to GND – 10V ≤ VIN ≤ 10V Output Low, IOUT = – 1.6mA (VCC = 5V) Output High, IOUT = 160µA (VCC = 5V) Sinking Current, VOUT = VCC Shutdown, 0 ≤ VOUT ≤ VCC (Note 3) IOUT = 0mA IOUT = 12mA IOUT = 0mA IOUT = – 12mA Shutdown to Turn-On Positive Negative ±9 ● 0.8 5 –5 ● ● ● ● MAX ±12 ±10 3.5 – 15 1.3 1.7 0.4 5 0.2 4.8 – 40 1 8.0 7.5 – 8.0 – 7.0 0.2 ±500 2.4 1.0 7 0.4 10 UNITS V V V V µA µA mA µA V V V kΩ V V mA µA V V V V ms 1349fa 2 LTC1349 DC ELECTRICAL CHARACTERISTICS The ● denotes specifications which apply over the full operating temperature range. VCC = 5V, C1 = C2 = C3 = C4 = 0.1µF, unless noted. PARAMETER Power Supply VCC Supply Current CONDITIONS No Load (All Drivers VIN = VCC)(Note 2), 0°C ≤ TA ≤ 70°C No Load (All Drivers VIN = 0V)(Note 2), 0°C ≤ TA ≤ 70°C No Load (All Drivers VIN = VCC)(Note 2), 0°C ≤ TA ≤ 85°C No Load (All Drivers VIN = VCC)(Note 2), – 40°C ≤ TA ≤ 0°C No Load (All Drivers VIN = 0V)(Note 2), – 40°C ≤ TA ≤ 85°C Shutdown (Note 3) Supply Leakage Current (VCC) On/Off Threshold Low On/Off Threshold High MIN TYP MAX UNITS 0.8 1.0 1.0 1.5 1.5 50 0.8 2.0 0.3 0.5 0.3 0.3 0.5 35 1.4 1.4 mA mA mA mA mA µA V V ● ● ● ● ● ● ● ● AC CHARACTERISTICS The ● denotes specifications which apply over the full operating temperature range. VCC = 5V, C1 = C2 = C3 = C4 = 0.1µF, unless noted. PARAMETER CONDITIONS Slew Rate RL = 3k, CL = 51pF RL = 3k, CL = 2500pF MIN TYP MAX UNITS 8 5 30 3 V/µs V/µs Driver Propagation Delay (TTL to RS232) t HLD (Figure 1) t LHD (Figure 1) ● ● 2 2 3.5 3.5 µs µs Receiver Propagation Delay (RS232 to TTL) t HLR (Figure 2) t LHR (Figure 2) ● ● 0.3 0.2 0.8 0.8 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. U W TYPICAL PERFOR A CE CHARACTERISTICS Driver Output Voltage Receiver Input Thresholds 2.2 10 6 OUTPUT HIGH VCC = 5V VCC = 4.5V 2 0 –2 OUTPUT LOW VCC = 4.5V 1.8 VTH 1.6 VTL 1.4 35 30 25 20 15 10 1.2 –6 5 VCC = 5V –8 –40 VCC = 5V RL = 3k CL = 2500pF 3 DRIVERS ACTIVE 40 2.0 4 –4 45 SUPPLY CURRENT (mA) RL = 3k THRESHOLD VOLTAGE (V) DRIVER OUTPUT VOLTAGE (V) 8 Supply Current vs Data Rate –20 20 0 40 60 TEMPERATURE (°C) 80 100 LTC1349 • TPC01 1.0 –40 –20 40 20 60 0 TEMPERATURE (˚C) 80 100 LTC1349 • TPC02 0 0 25 75 100 125 50 DATA RATE (k BAUD) 150 175 LTC1349 • TPC03 1349fa 3 LTC1349 U W TYPICAL PERFOR A CE CHARACTERISTICS 40 14 35 3 DRIVERS LOADED RL = 3k 10 8 1 DRIVER LOADED RL = 3k 6 4 2 20 18 30 25 VOUT = –20V 20 15 10 VOUT = 20V 5 0 SHORT-CIRCUIT CURRENT (mA) 16 12 Driver Short-Circuit Current Driver Leakage in Shutdown 45 LEAKAGE CURRENT (µA) SUPPLY CURRENT (mA) VCC Supply Current 20 10 30 20 40 50 TEMPERATURE (°C) 60 70 0 10 30 20 40 50 TEMPERATURE (°C) LTC1349 • TPC04 ISC+ 12 10 8 6 60 70 0 –40 LTC1349 • TPC05 Receiver Short-Circuit Current ISC– 14 4 0 0 16 –20 20 0 40 60 TEMPERATURE (°C) 80 100 LTC1349 • TPC06 Driver Output Waveforms Receiver Output Waveforms SHORT-CIRCUIT CURRENT (mA) 60 DRIVER OUTPUT RL = 3k CL = 2500pF 50 40 RECEIVER OUTPUT CL = 2500pF DRIVER OUTPUT RL = 3k ISC– INPUT 30 INPUT ISC+ 20 LTC1349 • TPC08 10 –40 –20 40 20 0 60 TEMPERATURE (°C) 80 LTC1349 • TPC09 100 LTC1349 • TPC07 U U U PI FU CTIO S VCC: 5V Input Supply Pin. Supply current is typically 35µA 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 Shutdown mode, with receivers 4 and 5 kept alive and the supply current equal to 35µA. All driver outputs and other receiver outputs are in high impedance state. This pin can not float. V +: Positive 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 5V. 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 –: Negative 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 charge pump efficiency, the capacitor’s effective series resistance should be less than 20Ω. 1349fa 4 LTC1349 U U U PI FU CTIO S 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. Receiver 1, 2 and 3 outputs are in a high impedance state when in Shutdown mode to allow data line sharing. Receivers 4 and 5 are kept alive in Shutdown. U W W SWITCHI G TI E WAVEFOR S VCC DRIVER INPUT 1.4V 1.4V 0V V+ DRIVER OUTPUT 0V 0V t LHD V– t HLD LTC1349 • F01 Figure 1. Driver Propagation Delay Timing VCC 1.7V RX INPUT RX OUTPUT 1.3V 0V 2.4V 0.8V t LHR t HLR VCC 0V LTC1349 • F02 Figure 2. Receiver Propagation Delay Timing TEST CIRCUITS Driver Timing Test Load DRIVER INPUT Receiver Timing Test Load DRIVER OUTPUT RX OUTPUT RX INPUT DRIVER 51pF 3k RX 51pF LTC1349 • TA04 LTC1349 • TA03 1349fa 5 LTC1349 TEST CIRCUITS ESD Test Circuit V+ C1 0.1µF VCC 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 1 2 28 LTC1349 V– 27 3 26 4 25 5 24 6 23 7 22 8 21 9 20 10 19 11 18 12 17 13 16 14 15 C3 0.1µF C4 0.1µF DRIVER 1 IN RX1 OUT DRIVER 2 IN RX2 OUT RX3 OUT RX4 OUT DRIVER 3 IN RX5 OUT GND NC NC LTC1349 • TC 1349fa 6 LTC1349 U PACKAGE DESCRIPTIO 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 7.8 – 8.2 5.3 – 5.7 0.42 ±0.03 7.40 – 8.20 (.291 – .323) 0.65 BSC 1 2 3 4 5 6 7 8 9 10 11 12 13 14 RECOMMENDED SOLDER PAD LAYOUT 5.00 – 5.60** (.197 – .221) 2.0 (.079) 0° – 8° 0.09 – 0.25 (.0035 – .010) 0.65 (.0256) BSC 0.55 – 0.95 (.022 – .037) 0.05 (.002) 0.22 – 0.38 (.009 – .015) NOTE: 1. CONTROLLING DIMENSION: MILLIMETERS MILLIMETERS 2. DIMENSIONS ARE IN (INCHES) G28 SSOP 0802 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 NW Package 28-Lead PDIP (Wide .600 Inch) (Reference LTC DWG # 05-08-1520) 1.467* (36.957) MAX 28 27 26 25 24 23 22 21 20 19 18 17 16 15 1 2 3 4 5 6 7 8 9 10 11 12 13 14 .505 – .560* (12.827 – 14.224) .600 – .625 (15.240 – 15.875) .008 – .015 (0.203 – 0.381) +.035 .625 –.015 ( 15.87 +0.889 –0.381 NOTE: 1. DIMENSIONS ARE ) .045 – .065 (1.143 – 1.651) .150 ± .005 (3.810 ± 0.127) .015 (0.381) MIN .070 (1.778) TYP .120 (3.175) MIN INCHES MILLIMETERS *THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .010 INCH (0.254mm) .035 – .080 (0.889 – 2.032) .100 (2.54) BSC .018 ± .003 (0.457 ± 0.076) NW28 1002 1349fa 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 LTC1349 U PACKAGE DESCRIPTIO SW Package 28-Lead Plastic Small Outline (Wide .300 Inch) (Reference LTC DWG # 05-08-1620) .050 BSC .045 ±.005 .030 ±.005 TYP .697 – .712 (17.70 – 18.08) NOTE 4 N 28 27 26 25 24 23 22 21 20 19 18 17 16 15 N .325 ±.005 .420 MIN .394 – .419 (10.007 – 10.643) NOTE 3 1 2 3 N/2 N/2 RECOMMENDED SOLDER PAD LAYOUT .005 (0.127) RAD MIN .009 – .013 (0.229 – 0.330) .291 – .299 (7.391 – 7.595) NOTE 4 .010 – .029 × 45° (0.254 – 0.737) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 .037 – .045 (0.940 – 1.143) .093 – .104 (2.362 – 2.642) 0° – 8° TYP .050 (1.270) BSC NOTE 3 .004 – .012 (0.102 – 0.305) .014 – .019 (0.356 – 0.482) TYP .016 – .050 (0.406 – 1.270) NOTE: 1. DIMENSIONS IN 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 DESCRIPTION COMMENTS LT ®1137A 5V, 3 Driver, 5 Receiver RS232 Transceiver ±15kV ESD per IEC 1000-4 LTC1327 3.3V, 3 Driver, 5 Receiver RS562 Transceiver 300µA Supply Current, 0.2µA in Shutdown LTC1337 5V, 3 Driver, 5 Receiver RS232 Transceiver 300µA Supply Current, 1µA in Shutdown LTC1348 3.3V to 5V, 3 Driver, 5 Receiver RS232 Transceiver True RS232 on 3.3V, 5 Receivers Active in Shutdown 1349fa 8 Linear Technology Corporation LW/TP 1102 1K REV A • PRINTED IN USA 1630 McCarthy Blvd., Milpitas, CA 95035-7487 (408) 432-1900 ● FAX: (408) 434-0507 ● WWW.linear.com LINEAR TECHNOLOGY CORPORATION 1993