LT1039/LT1039-16 RS232 Driver/Receiver with Shutdown U FEATURES ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ DESCRIPTIO Operates from ±5V to ±15V Supplies Fully Protected Against Overload Outputs Can Be Driven ±30V Without Damage Three-State Outputs; Outputs Open When Off Bipolar Circuit—No Latchup ±30V Input Range Triple Driver/Receiver No Supply Current in Shutdown 30kΩ Input Impedance Meets All RS232 Specifications 16-Pin Version—Pin Compatible with MC145406 Available in SO Package 15kV ESD: LT1039A The LT ®1039 is a triple RS232 driver/receiver that includes shutdown. Each receiver will accept up to ±30V input and can drive either TTL or CMOS logic. The RS232 drivers accept TTL logic inputs and output RS232 voltage levels. The outputs are fully protected against overload and can be shorted to ground or up to ±30V without damage to the drivers. Additionally, when the system is shut down or power is off, the outputs are in a high impedance state allowing data line sharing. Bipolar circuitry makes this driver/receiver exceptionally rugged against overloads or ESD damage. A BIAS pin allows one receiver to be kept on while the rest of the part is shut down. U APPLICATIO S The LT1039 is also available in the 16-pin version, without shutdown or BIAS pin functions. RS232 Interface Terminals Modems For applications requiring operation from a single 5V supply, see the LT1080A/LT1081A, LT1180A/LT1181A and LT1130A data sheets. For applications requiring 15kV ESD, see the LT1039A. ■ ■ ■ , LTC and LT are registered trademarks of Linear Technology Corporation. U TYPICAL APPLICATIO 12V BIAS* RS232 IN 1 V+ 2 LT1039 VCC 18 17 16 3 Driver Output Swing 5V V+ ON/OFF LOGIC POSITIVE – 0.5 RS232 OUT RS232 IN 4 15 5 14 LOGIC LOGIC 30k RS232 OUT RS232 IN 6 13 7 12 LOGIC LOGIC OUTPUT VOLTAGE (V) 30k 1.5 NEGATIVE 1.0 0.5 30k *BIAS PIN USED RS232 OUT TO KEEP THE RECEIVER ON – 12V WHILE IN SHUTDOWN 11 8 9 V– GND 1039 TA01 10 LOGIC V– 0 2 6 8 4 OUTPUT CURRENT (mA) 10 1039 TA02 1 LT1039/LT1039-16 W W U W ABSOLUTE MAXIMUM RATINGS (Note 1) Supply Voltage Driver (V +, V –) ................................................. ±16V Receiver (VCC) ...................................................... 7V Logic Inputs .................................................. V – to 25V Receiver Inputs ..................................................... ±30V ON/OFF Input .............................................. GND to 12V Driver Outputs ....................... (V – + 30V) to (V + – 30V) Short-Circuit Duration ..................................... Indefinite Operating Temperature Range LT1039C .................................................. 0°C to 70°C LT1039I ............................................. – 40°C to 85°C LT1039M ......................................... – 55°C to 125°C Storage Temperature Range ................. – 65°C to 150°C Lead Temperature (Soldering, 10 sec).................. 300°C U W U PACKAGE/ORDER INFORMATION ORDER PART NUMBER TOP VIEW V+ 1 16 VCC REC1 IN 2 15 REC1 OUT TR1 OUT 3 14 TR1 IN REC2 IN 4 13 REC2 OUT TR2 OUT 5 12 TR2 IN REC3 IN 6 11 REC3 OUT TR3 OUT 7 10 TR3 IN V– 8 9 J PACKAGE 16-LEAD CERDIP LT1039CN16 LT1039CSW16 LT1039MJ16 GND N PACKAGE 16-LEAD PDIP 1 18 VCC BIAS 2 17 ON/OFF REC1 IN 3 16 REC1 OUT TR1 OUT 4 15 TR1 IN REC2 IN 5 14 REC2 OUT TR2 OUT 6 13 TR2 IN REC3 IN 7 12 REC3 OUT TR3 OUT 8 11 TR3 IN V– 9 10 GND LT1039CJ LT1039CN LT1039CSW LT1039IN LT1039ISW LT1039MJ N PACKAGE 18-LEAD PDIP J PACKAGE 18-LEAD CERDIP SW PACKAGE 16-LEAD PLASTIC SO WIDE ORDER PART NUMBER TOP VIEW V+ SW PACKAGE 18-LEAD PLASTIC SO WIDE TJMAX = 150°C, θJA = 100°C/ W (J) TJMAX = 150°C, θJA = 140°C/ W (N) TJMAX = 150°C, θJA = 150°C/ W (SW) TJMAX = 150°C, θJA = 100°C/ W(J) TJMAX = 150°C, θJA = 120°C/ W(N) TJMAX = 150°C, θJA = 120°C/ W(SW) ELECTRICAL CHARACTERISTICS The ● denotes specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. PARAMETER CONDITIONS MIN TYP MAX UNITS Driver V + = 12V, V – = – 12V, VON/OFF = 2.5V (Note 2) Output Voltage Swing Logic Input Voltage Levels Load = 3k to Ground Positive Negative ● ● V + – 0.4 V – + 1.5 V + – 0.1 V – + 1.0 Input Low Level (VOUT = High) Input High Level (VOUT = Low) ● ● 1.4 1.4 0.8 2.0 V V 1 5 20 20 µA µA V V Logic Input Current VIN ≥ 2.0V VIN ≤ 0.8V Output Short-Circuit Current Sourcing Current, VOUT = 0V Sinking Current, VOUT = 0V Output Leakage Current Shutdown (Notes 3, 4), VOUT = ±18V, VIN = 0V ● 10 (25°C) 200 µA Supply Leakage Current Shutdown (Note 3) ● 1 (25°C) 100 µA Slew Rate RL = 3k, CL = 51pF 15 30 V/µs Supply Current VOUT = Low 4 8 mA 2 5 –5 4 15 – 15 mA mA LT1039/LT1039-16 ELECTRICAL CHARACTERISTICS The ● denotes specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. PARAMETER CONDITIONS MIN TYP MAX UNITS ● ● 0.5 1.3 1.7 2.8 V V ● 0.1 0.4 1.0 V Receiver VCC = 5V, VON/OFF = 2.5V (Note 2) Input Voltage Thresholds Input Low Level (VOUT = High) Input High Level (VOUT = Low) Hysteresis Input Resistance ● 30 Output Low, IOUT = – 1.6mA Output High, IOUT = 160µA ● ● 3.5 0.4 4.8 Output Short-Circuit Current Sourcing Current, VOUT = 0V (Note 5) Sinking Current, VOUT = VCC ● ● 0.5 –10 Output Leakage Current Shutdown (Note 2), 0V ≤ VOUT ≤ VCC, VIN = 0V ● 1 10 µA ● 4 7 mA Output Voltage Supply Current Supply Leakage Current Shutdown (Note 3) ● ON/OFF Pin Current 0V ≤ VON/OFF ≤ 5V ● Note 1: Absolute Maximum Ratings are those values beyond which the life of a device by be impaired. Note 2: VON/OFF = 5V for LT1039M grade devices. Note 3: VON/OFF = 0.4V for – 55°C ≤ TA ≤ 100°C and VON/OFF = 0.2V for 100°C ≤ TA ≤ 125°C. Does not apply to LT1039-16 part. kΩ 0.5 V V 1 mA mA 1 (25°C) – 15 100 µA 80 µA Note 4: For TA ≥ 100°C, leakage current is 350µA max. Note 5: For TA ≤ – 25°C, output source current is 0.4mA. U W TYPICAL PERFORMANCE CHARACTERISTICS Receiver Input Thresholds ON/OFF Pin Thresholds 5.0 45 2.75 4.5 40 2.50 4.0 35 2.25 30 25 SINKING 20 15 SOURCING 2.00 ON/OFF PIN VOLTAGE (V) 3.00 INPUT VOLTAGE (V) OUTPUT CURRENT (mA) Driver Output Short-Circuit Current 50 INPUT HIGH 1.75 1.50 1.25 INPUT LOW 3.5 3.0 2.5 2.0 10 1.00 1.0 5 0.75 0.5 0 –55 –25 50 25 0 75 TEMPERATURE (°C) 100 125 1039 G01 0.50 –55 –25 50 25 0 75 TEMPERATURE (°C) 100 125 1039 G02 MINIMUM ON VOLTAGE 1.5 MINIMUM OFF VOLTAGE 0 –55 –25 50 25 0 75 TEMPERATURE (°C) 100 125 1039 G03 3 LT1039/LT1039-16 U W TYPICAL PERFORMANCE CHARACTERISTICS Driver Output Leakage in Shutdown Supply Current in Shutdown 1000 1000 SUPPLY CURRENT MEASURED INTO VCC AND V + 10 0 25 50 75 TEMPERATURE (°C) 100 OUTPUT CURRENT (mA) 100 1 –55 –25 100 OUTPUT SINKING OUTPUT LEAKAGE CURRENT (µA) SUPPLY CURRENT (nA) Receiver Output Short-Circuit Current 100 VOUT – 30V 10 1 –55 –25 125 0 25 50 75 TEMPERATURE (°C) 100 ON/OFF Pin Current vs Voltage OUTPUT VOLTAGE REFERRED TO SUPPLIES (V) INPUT CURRENT (µA) 30 25 20 15 10 5 0 –5 2 3 INPUT VOLTAGE (V) 0.1 –55 –25 4 V+ – 0.2 OUTPUT HIGH – 0.4 1.2 1.0 OUTPUT LOW 0.8 0.6 0.4 0.2 V– 5 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 OUTPUT CURRENT (mA) 1039 G08 Output Waveforms Shutdown to Driver Output 10V 5V 0V DRIVER OUTPUT 10V 0V DRIVER OUTPUT OUTPUT LOW – 5V – 10V V + = 12V V – = –12V VCC = 5V RL = 3k 2µs/DIV 1039 G09 DRIVER OUTPUT CONNECTED TO RECEIVER INPUT 4 OUTPUT HIGH 5V 0V 0V DRIVER OUTPUT – 10V 5V INPUT 0V ON/OFF INPUT 5V 0V V + = 12V V – = –12V RL = 3k 100 125 1039 G06 1039 G07 RECEIVER OUTPUT 0 25 50 75 TEMPERATURE (°C) Driver Output Swing vs Current 35 1 125 1039 G05 40 0 OUTPUT SOURCING 1 VOUT 30V 1039 G04 –10 10 1ms/DIV 1039 G10 LT1039/LT1039-16 U W TYPICAL PERFORMANCE CHARACTERISTICS Shutdown to Receiver Output BIAS Pin Response Time 6V 6V RECEIVER 4V OUTPUT 2V RECEIVER 1 4V OUTPUT 2V 0V 0V ON/OFF 5V INPUT 0V BIAS INPUT 5V (THRU 25kΩ) 0V VCC = 5V U U U PIN FUNCTIONS 1ms/DIV 1039 G11 VCC = 5V 0.2µs/DIV 1039 G12 (Pin numbers listed are for 18-pin device) V +, V – (Pins 1, 9): Driver Supply Pins. Supply current drops to zero in shutdown mode. Driver outputs are in a high impedance state when V + and V – = 0V. BIAS (Pin 2): Keeps receiver 1 on while the LT1039 is in the shutdown mode. Leave BIAS pin open when not in use. See Applications Information for proper use. REC IN (Pins 3, 5, 7): Receiver Input Pins. Accepts RS232 voltage levels (±30V) and has 0.4V of hysteresis to provide noise immunity. Input impedance is nominally 30kΩ. TR OUT (Pins 4, 6, 8): Driver Outputs with RS232 Voltage Levels. Outputs are in a high impedance state when in the shutdown mode or when power is off (V + and V – = 0V) to allow data line sharing. Outputs are fully short-circuit protected from V – + 30V to V + – 30V with power on, off or in the shutdown mode. Typical output breakdowns are greater than ±45V and higher applied voltages will not damage the device if moderately current limited. GND (Pin 10): Ground Pin. TR IN (Pins 11, 13, 15): RS232 Driver Input Pins. Inputs are TTL/CMOS compatible. Inputs should not be allowed to float. Tie unused inputs to VCC. REC OUT (Pins 12, 14, 16): Receiver Outputs with TTL/ CMOS Voltage Levels. Outputs are in a high impedance state when in the shutdown mode to allow data line sharing. Outputs are fully short-circuit protected to ground or VCC with power on, off or in the shutdown mode. ON/OFF (Pin 17): Controls the operation mode of the LT1039 and is TTL/CMOS compatible. A logic low puts the device in the shutdown mode which reduces input supply current to zero and places both driver and receiver outputs in a high impedance state. VCC (Pin 18): 5V Power for Receivers. 5 LT1039/LT1039-16 U U W U APPLICATIONS INFORMATION The driver output stage of the LT1039 offers significantly improved protection over older bipolar and CMOS designs. In addition to current limiting, the driver output can be externally forced to ±30V with no damage or excessive current flow, and will not disrupt the supplies. Sharing a Receiver Line RS232 INPUT A LT1039 #1 RECEIVER RS232 INPUT B LT1039 #2 RECEIVER LT1039 Driver 30V LOGIC OUTPUT LT1039 OUTPUT CAN BE FORCED EXTERNALLY – 30V LOGIC INVERTER 1039 AI01 Some drivers have diodes connected between the outputs and the supplies, so externally applied voltages can cause excessive supply voltage to develop ON/OFF (CHANNEL SELECT) INPUT 1039 AI04 Transceiver Older RS232 Drivers and Other CMOS Drivers V+ WITH SOME DRIVERS, EXTERNALLY APPLIED VOLTAGE CAN FORCE THE SUPPLIES V– LOGIC TRANSMIT/RECEIVE LINE LT1039 #2 RECEIVER 1039 AI02 Placing the LT1039 in the shutdown mode (Pin 17 low) puts both the driver and receiver outputs in a high impedance state. This allows data line sharing and transceiver applications. RS232 TRANSMIT/RECEIVE LINE LT1039 #1 DRIVER LOGIC INVERTER ON/OFF (TRANSMIT/RECEIVE) INPUT 1039 AI05 Sharing a Transmitter Line The shutdown mode also drops all supply currents (VCC, V +, V –) to zero for power conscious systems. LOGIC INPUT A LT1039 #1 DRIVER LOGIC INPUT B LT1039 #2 DRIVER RS232 TRANSMISSION LINE LOGIC INVERTER ON/OFF (CHANNEL SELECT) INPUT 6 1039 AI03 LT1039/LT1039-16 U U W U APPLICATIONS INFORMATION When driving CMOS logic from a receiver that will be used in the shutdown mode and there is no other active receiver on the line, a 51k resistor can be placed from the logic input to VCC to force a definite logic level when the receiver output is in a high impedance state. Driving CMOS Logic from a Receiver CMOS LOGIC LT1039 RECEIVER RS232 INPUT Input Overvoltage Protection RECEIVER 1k 30k 30V 5.6k 25k 2 BIAS 1039A AI06 To protect against receiver input overloads in excess of ±30V, a voltage clamp can be placed on the data line and still maintain RS232 compatibility. RS232 INPUT LOGIC SHUTDOWN INPUT LOGIC OUTPUT *FORCES LOGIC INPUT STATE WHEN VON/OFF IS LOW ON/OFF INPUT The BIAS pin is used to “keep alive” one receiver while in the shutdown mode (all other circuitry being inactive). This allows a system to be in shutdown and still have one active receiver for transferring data. Keeping Alive One Receiver While in Shutdown VCC 51k* Driver inputs should not be allowed to float. Any unused inputs should be tied to VCC. LOGIC OUTPUT RS232 INPUT ON/OFF 3 17 16 LOGIC OUTPUT LT1039 1039 AI09 It can also be used to make an RS232 compatible shutdown control line. Driving the BIAS pin low through a resistance of 24k to 30k keeps the receiver active. Do not drive the BIAS pin directly from a logic output without the series resistor. An unused BIAS pin should be left open. 30V 1039 AI07 The receiver input impedance of the LT1039 is nominally 30kΩ. For applications requiring a 5kΩ input impedance, a 5.6k resistor can be connected from the receiver input to ground. 5kΩ Impedance Matching RS232 Compatible Shutdown Control Line 25k 2 BIAS RS232 SHUTDOWN INPUT ON/OFF 3 17 16 LT1039 1039A AI10 RECEIVER RS232 INPUT 30k 5.6k LOGIC OUTPUT 1039 AI08 7 LT1039/LT1039-16 U PACKAGE DESCRIPTION Dimensions in inches (millimeters) unless otherwise noted. J Package 16-Lead CERDIP (Narrow 0.300, Hermetic) (LTC DWG # 05-08-1110) CORNER LEADS OPTION (4 PLCS) 0.840 (21.336) MAX 0.005 (0.127) MIN 0.023 – 0.045 (0.584 – 1.143) HALF LEAD OPTION 0.045 – 0.068 (1.143 – 1.727) FULL LEAD OPTION 16 15 14 12 13 10 11 9 0.220 – 0.310 (5.588 – 7.874) 0.025 (0.635) RAD TYP 2 1 3 5 4 6 7 8 0.200 (5.080) MAX 0.300 BSC (0.762 BSC) 0.015 – 0.060 (0.380 – 1.520) 0.008 – 0.018 (0.203 – 0.457) 0° – 15° NOTE: LEAD DIMENSIONS APPLY TO SOLDER DIP/PLATE OR TIN PLATE LEADS 0.045 – 0.068 (1.143 – 1.727) 0.125 (3.175) MIN 0.100 ± 0.010 (2.540 ± 0.254) 0.014 – 0.026 (0.360 – 0.660) J16 1197 J Package 18-Lead CERDIP (Narrow 0.300, Hermetic) (LTC DWG # 05-08-1110) CORNER LEADS OPTION (4 PLCS) 0.023 – 0.045 (0.584 – 1.143) HALF LEAD OPTION 0.045 – 0.068 (1.143 – 1.727) FULL LEAD OPTION 0.005 (0.127) MIN 0.960 (24.384) MAX 18 17 16 15 14 13 12 11 10 0.220 – 0.310 (5.590 – 7.870) 0.025 (0.635) RAD TYP 1 2 3 4 5 6 7 8 9 0.200 (5.080) MAX 0.300 BSC (0.762 BSC) 0.015 – 0.060 (0.380 – 1.520) 0.008 – 0.018 (0.203 – 0.457) 0° – 15° NOTE: LEAD DIMENSIONS APPLY TO SOLDER DIP/PLATE OR TIN PLATE LEADS 0.125 (3.175) MIN 0.045 – 0.068 (1.143 – 1.727) 0.100 ± 0.010 (2.540 ± 0.254) 0.014 – 0.026 (0.360 – 0.660) J18 1197 8 LT1039/LT1039-16 U PACKAGE DESCRIPTION Dimensions in inches (millimeters) unless otherwise noted. N Package 16-Lead PDIP (Narrow 0.300) (LTC DWG # 05-08-1510) 0.770* (19.558) MAX 16 15 14 13 12 11 10 9 1 2 3 4 5 6 7 8 0.255 ± 0.015* (6.477 ± 0.381) 0.130 ± 0.005 (3.302 ± 0.127) 0.300 – 0.325 (7.620 – 8.255) 0.020 (0.508) MIN 0.009 – 0.015 (0.229 – 0.381) ( +0.035 0.325 –0.015 8.255 +0.889 –0.381 0.045 – 0.065 (1.143 – 1.651) ) 0.065 (1.651) TYP 0.125 (3.175) MIN 0.018 ± 0.003 (0.457 ± 0.076) 0.100 ± 0.010 (2.540 ± 0.254) *THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.010 INCH (0.254mm) N16 1197 N Package 18-Lead PDIP (Narrow 0.300) (LTC DWG # 05-08-1510) 0.900* (22.860) MAX 18 17 16 15 14 13 12 11 10 1 2 3 4 5 6 7 8 9 0.255 ± 0.015* (6.477 ± 0.381) 0.130 ± 0.005 (3.302 ± 0.127) 0.300 – 0.325 (7.620 – 8.255) 0.009 – 0.015 (0.229 – 0.381) +0.035 0.325 –0.015 0.045 – 0.065 (1.143 – 1.651) 0.020 (0.508) MIN 0.065 (1.651) TYP 0.005 (0.127) MIN 0.100 ± 0.010 (2.540 ± 0.254) *THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.010 INCH (0.254mm) ( +0.889 8.255 –0.381 ) 0.125 (3.175) MIN 0.018 ± 0.003 (0.457 ± 0.076) N18 1197 9 LT1039/LT1039-16 U PACKAGE DESCRIPTION Dimensions in inches (millimeters) unless otherwise noted. SW Package 16-Lead Plastic Small Outline (Wide 0.300) (LTC DWG # 05-08-1620) 0.398 – 0.413* (10.109 – 10.490) 16 15 14 13 12 11 10 9 0.394 – 0.419 (10.007 – 10.643) NOTE 1 1 0.291 – 0.299** (7.391 – 7.595) 2 3 4 5 6 7 0.093 – 0.104 (2.362 – 2.642) 0.010 – 0.029 × 45° (0.254 – 0.737) 8 0.037 – 0.045 (0.940 – 1.143) 0° – 8° TYP 0.009 – 0.013 (0.229 – 0.330) NOTE 1 0.016 – 0.050 (0.406 – 1.270) 0.050 (1.270) TYP 0.014 – 0.019 (0.356 – 0.482) TYP NOTE: 1. 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 *DIMENSION DOES NOT INCLUDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE **DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE 10 0.004 – 0.012 (0.102 – 0.305) S16 (WIDE) 0396 LT1039/LT1039-16 U PACKAGE DESCRIPTION Dimensions in inches (millimeters) unless otherwise noted. SW Package 18-Lead Plastic Small Outline (Wide 0.300) (LTC DWG # 05-08-1620) 0.447 – 0.463* (11.354 – 11.760) 18 17 16 15 14 13 12 11 10 0.394 – 0.419 (10.007 – 10.643) SEE NOTE 0.291 – 0.299** (7.391 – 7.595) 1 2 3 4 5 6 7 8 9 0.093 – 0.104 (2.362 – 2.642) 0.010 – 0.029 × 45° (0.254 – 0.737) 0.037 – 0.045 (0.940 – 1.143) 0° – 8° TYP 0.009 – 0.013 (0.229 – 0.330) NOTE 1 0.016 – 0.050 (0.406 – 1.270) 0.050 (1.270) TYP 0.004 – 0.012 (0.102 – 0.305) 0.014 – 0.019 (0.356 – 0.482) TYP NOTE: 1. 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 S18 (WIDE) 0396 *DIMENSION DOES NOT INCLUDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE **DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE 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. 11 LT1039/LT1039-16 U TYPICAL APPLICATION LT1080A (Driver/Receiver with Power Supply) Driving an LT1039 SHUTDOWN 5V 18 ON/OFF VCC LT1080A 17 18 VCC ON/OFF LT1039 17 TTL IN RS232 OUT TTL IN RS232 OUT TTL IN RS232 OUT TTL IN RS232 OUT TTL IN RS232 OUT RS232 IN TTL OUT RS232 IN TTL OUT 5k 30k RS232 IN TTL OUT RS232 IN TTL OUT 5k 1µF + 1µF 2 C1+ 4 C1– 5 C2+ 6 C2– RS232 IN TTLOUT GND V+ 3 V– 7 16 + 1µF 1 V+ 9 V– 1µF + + 30k 30k GND 10 1039 TA03 RELATED PARTS PART NUMBER ® DESCRIPTION COMMENTS LTC 485 Low Power RS485 Transceiver Industry Standard LT1039A/LT1039A-16 Triple RS232 Driver/Receiver with Shutdown ±15kV ESD Protection LT1137A 5V 3-Driver/5-Receiver RS232 Transceiver ±15kV ESD Protection LT1180A/LT1181A 5V 2-Driver/2-Receiver RS232 Transceiver Industry Standard, 0.1µF Capacitors LTC1345 V.35 Transceiver Single 5V Supply Using 0.1µF Capacitors LTC1348 3.3V 3-Driver/5-Receiver RS232 Transceiver Operates from 3.3V to 5V Supplies, 5 Receivers Active in Shutdown 12 Linear Technology Corporation 1039fc LT/TP 0599 2K REV C • PRINTED IN USA 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408)432-1900 ● FAX: (408) 434-0507 ● www.linear-tech.com LINEAR TECHNOLOGY CORPORATION 1991