LTC1385 3.3V Low Power EIA/TIA-562 Transceiver U DESCRIPTIO FEATURES ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ Operates from a Single 3.3V Supply Low Supply Current: ICC = 200µA ICC = 35µA in Driver Disable Mode ICC = 0.2µA in Shutdown Mode ESD Protection Over ±10kV Uses Small Capacitors: 0.1µF Operates to 120kBaud Output Overvoltage Does Not Force Current Back into Supplies EIA/TIA-562 I/O Lines Can Be Forced to ±25V Without Damage Pin Compatible with LT1180A The LTC1385 is an ultra-low power, 2-driver/2-receiver EIA / TIA-562 transceiver which operates from a single 3.3V supply. The charge pump requires only four spacesaving 0.1µF capacitors. The transceiver operates in one of three modes: Normal, Driver Disable or Shutdown. In the Normal mode, ICC is only 200µA in the unloaded condition. In the Driver Disable mode, the charge pump is turned off, the driver outputs are forced into three-state, both receivers are kept active, and ICC drops to 35µA. In the Shutdown mode, everything is turned off and ICC drops to 0.2µA. The LTC1385 is fully compliant with all data rate and overvoltage EIA / TIA-562 specifications. The transceiver can operate up to 120kbaud with a 1000pF, 3kΩ load. Both driver outputs and receiver inputs can be forced to ±25V without damage, and can survive multiple ±10kV ESD strikes. UO APPLICATI ■ Notebook Computers Palmtop Computers UO ■ S TYPICAL APPLICATI 2-Drivers/2-Receivers with Shutdown and Driver Disable 0.1µF LTC1385 4 LOGIC INPUT 6 VCC 15 VCC LOGIC INPUT LOGIC OUTPUT LOGIC OUTPUT 0.1µF 300k 12 8 13 14 5k 10 5k ON/OFF 562 OUTPUT 300k 11 18 9 1.2 500 1.0 562 OUTPUT 562 INPUT 562 INPUT 16 0.1µF 400 0.8 QUIESCENT CURRENT 300 0.6 0.4 200 100 SHUTDOWN CURRENT 0 –20 0 20 40 TEMPERATURE (°C) 60 SHUTDOWN CURRENT (µA) 0.1µF 3 7 5 600 VCC = 3.3V QUIESCENT CURRENT (µA) 17 2 Quiescent and Shutdown Supply Current vs Temperature 0.2 0 80 TEST CONDITION: VCC = 3.3V 1 LTC1385 • TA02 DRIVER DISABLE LTC1385 • TA01 1 LTC1385 W W W AXI U U ABSOLUTE RATI GS Supply Voltage (VCC) ................................................ 5V 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 .................... 0°C to 70°C Storage Temperature Range ................ – 65°C to 150°C Lead Temperature (Soldering, 10 sec)................. 300°C U W U PACKAGE/ORDER I FOR ATIO TOP VIEW DRIVER DISABLE C1 + 1 20 ON/OFF 2 19 VCC V+ 3 18 GND C1 – 4 17 TR1 OUT C2 + 5 16 RX1 IN C2 – 6 15 RX1 OUT V– 7 14 TR1 IN TR2 OUT 8 13 TR2 IN RX2 IN 9 12 RX2 OUT NC 10 ORDER PART NUMBER LTC1385CG 11 NC ORDER PART NUMBER TOP VIEW DRIVER DISABLE 1 C1+ 2 18 ON/OFF 17 VCC V+ 3 C1– LTC1385CN LTC1385CS 16 GND 15 TR1 OUT 4 C2+ 5 14 RX1 IN C2 – 6 13 RX1 OUT V– 7 12 TR1 IN TR2 OUT 8 11 TR2 IN 10 RX2 OUT RX2 IN 9 N PACKAGE S PACKAGE 18-LEAD PLASTIC DIP 18-LEAD PLASTIC SOL G PACKAGE 20-LEAD SSOP TJMAX = 125°C, θJA = 85°C/W TJMAX = 125°C, θJA = 135°C/W Consult factory for Industrial and Military grade parts. DC ELECTRICAL CHARACTERISTICS VCC = 3.3V, C1 = C2 = C3 = C4 = 0.1µF, VON/OFF = VCC, Driver Disable = VCC, unless otherwise noted. PARAMETER CONDITIONS Any Driver Output Voltage Swing 3k to GND Logic Input Voltage Level Logic Input Current Output Short-Circuit Current Output Leakage Current 2 MIN TYP 4.5 – 4.5 1.4 1.4 Positive Negative ● ● 3.7 – 3.7 Input Low Level (VOUT = High) Input High Level (VOUT = Low) VIN = VCC VIN = 0V VOUT = 0V Shutdown or Driver Disable or VCC = 0V (Note 3,4), VOUT = ±20V ● ● 2.0 ● ● ● – 20 ±10 ±10 MAX 0.8 5 – 40 ±500 UNITS V V V V µA µA mA µA LTC1385 DC ELECTRICAL CHARACTERISTICS VCC = 3.3V, C1 = C2 = C3 = C4 = 0.1µF, VON/OFF = VCC, Driver Disable = VCC, unless otherwise noted. PARAMETER 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 Power Supply VCC Supply Current Supply Leakage Current (VCC) CONDITIONS Input Low Threshold Input High Threshold – 10V ≤ VIN ≤ 10V Output Low, IOUT = – 1.6mA (VCC = 3.3V) Output High, IOUT = 160µA (VCC = 3.3V) Sinking Current, VOUT = VCC Sourcing Current, VOUT = 0V Shutdown (Note 4), 0V ≤ VOUT ≤ VCC No Load (Note 2) Shutdown (Note 4) Driver Disable (Note 3) AC CHARACTERISTICS Driver Propagation Delay (TTL to EIA / TIA-562) Receiver Propagation Delay (EIA / TIA-562 to TTL) TYP ● ● 0.8 ● 0.1 3 1.3 1.7 0.4 5 0.2 3.2 – 20 7 1 ● ● 3.0 –5 2 ● IOUT = 0mA IOUT = 5mA IOUT = 0mA IOUT = – 5mA Shutdown or Driver Disable to Turn-On Digital Input Threshold Low Digital Input Threshold High PARAMETER Slew Rate MIN MAX 2.4 1.0 7 0.4 10 5.7 5.5 – 5.3 – 5.0 0.2 ● ● ● ● ● 2.0 UNITS V V V kΩ V V mA mA µA V V V V ms 0.2 0.2 35 1.4 1.4 0.5 10 50 0.8 mA µA µA V V TYP 8 5 2 2 0.3 0.2 MAX 30 UNITS V/µs V/µs µs µs µs µs VCC = 3.3V, C1 = C2 = C3 = C4 = 0.1µF, unless otherwise noted. CONDITIONS RL = 3k, CL = 51pF RL = 3k, CL = 1000pF t HLD (Figure 1) t LHD (Figure 1) t HLR (Figure 2) t LHR (Figure 2) The ● denotes specifications which apply over the operating temperature range 0°C ≤ TA ≤ 70°C. 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. MIN 3 ● ● ● ● 3.5 3.5 0.8 0.8 Note 3: Measurements made in the Driver Disable mode are performed with VDRIVER DISABLE = GND and VON/OFF = VCC. Note 4: Measurements made in the Shutdown mode are performed with VON/OFF = 0V. 3 LTC1385 U W TYPICAL PERFORMANCE CHARACTERISTICS Driver Output Voltage vs Temperature Receiver Input Thresholds vs Temperature 5 OUTPUT HIGH VCC = 3.3V 2 1 ALL DRIVERS WITH LOAD RL = 3k 0 –1 –2 OUTPUT LOW VCC = 3.3V –3 –4 1.8 VTH+ 1.6 1.4 VTH– 40 30 20 50 TEMPERATURE (°C) 60 70 0 10 40 30 50 20 TEMPERATURE (˚C) 60 LTC1385 • TPC01 5 70 0 Driver Leakage in Shutdown vs Temperature 18 40 16 LEAKAGE CURRENT (µA) 2.5 1 DRIVER LOADED RL = 3k 2.0 1.5 1.0 35 30 25 VOUT = –20V 20 15 10 VOUT = 20V 5 0.5 SHORT-CIRCUIT CURRENT (mA) 45 3.0 0 10 20 30 50 40 TEMPERATURE (°C) 60 0 70 10 30 20 40 50 TEMPERATURE (°C) Receiver Short-Circuit Current vs Temperature 60 70 40 35 30 ISC+ 6 4 0 0 10 50 30 40 20 TEMPERATURE (°C) 60 70 LTC1385 • TPC06 INPUT 15 INPUT ISC+ 10 LTC1385 • TPC08 5 0 0 10 50 30 40 20 TEMPERATURE (°C) 60 70 LTC1385 • TPC06 4 8 RECEIVER OUTPUT CL = 51pF DRIVER OUTPUT RL = 3k ISC– ISC– Receiver Output Waveform DRIVER OUTPUT RL = 3k CL = 1000pF 20 12 10 Driver Output Waveforms 45 25 14 LTC1385 • TPC05 LTC1385 • TPC04 140 2 0 0 120 Driver Short-Circuit Current vs Temperature 4.0 2 DRIVERS LOADED RL = 3k 80 100 60 DATA RATE (kBAUD) 40 LTC1385 • TPC03 4.5 3.5 20 LTC1385 • TPC02 VCC Supply Current vs Temperature SUPPLY CURRENT (mA) 10 0 1.0 10 15 1.2 –5 0 VCC = 3.3V RL = 3k CL = 2500pF ALL DRIVERS ACTIVE 2.0 SUPPLY CURRENT (mA) 3 THRESHOLD VOLTAGE (V) DRIVER OUTPUT VOLTAGE (V) 4 SHORT-CIRCUIT CURRENT (mA) Supply Current vs Data Rate 20 2.2 LTC1385 • TPC09 LTC1385 U U U PI FU CTIO S VCC: 3.3V Input Supply Pin. 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 independent of the Driver Disable pin. The supply current drops to 0.2µA and all driver and receiver outputs are forced into three-state. DRIVER DISABLE: TTL/CMOS Compatible Input Pin. With the ON/OFF pin held high, a logic low forces the part into the Driver Disable mode with the charge pump turned off and the driver outputs forced into three-state. Both receivers remain active and the supply current drops to 35µA. A logic high forces the part into the Normal mode. V +: Positive Supply Output (EIA/TIA-562 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 share a common capacitor. For a large number of devices, increasing the size of the shared common storage capacitors is recommended to reduce ripple. V –: Negative Supply Output (EIA/TIA-562 Drivers). V – ≅ – (2VCC – 1.3V). 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 2Ω. TR IN: EIA/TIA-562 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. To minimize power consumption, the internal driver pull-up resistors are disconnected from VCC in the Shutdown mode. TR OUT: Driver Outputs at EIA/TIA-562 Voltage Levels. Outputs are in a high impedance state when in the Shutdown or Driver Disable 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. Outputs are in a high impedance state when in the Shutdown mode. U W W SWITCHI G TI E WAVEFOR S DRIVER INPUT VCC 1.4V 1.4V 0V V+ DRIVER OUTPUT 0V 0V t LHD V – t HLD VCC 1.7V RX INPUT RX OUTPUT 1.3V 0V 2.4V 0.8V t LHR t HLR 0V 1385 F02 1385 F01 Figure 1. Driver Propagation Delay Timing VCC Figure 2. Receiver Propagation Delay Timing 5 LTC1385 TEST CIRCUITS Driver Timing Test Load DRIVER INPUT Receiver Timing Test Load RX OUTPUT DRIVER OUTPUT RX INPUT DRIVER 51pF RX 51pF 3k 1385 F04 1385 F03 ESD Test Circuit 17 2 0.1µF LTC1385 4 LOGIC INPUT 6 VCC LOGIC OUTPUT LOGIC OUTPUT 0.1µF 300k 15 12 VCC LOGIC INPUT 0.1µF 562 OUTPUT 300k 11 8 13 14 5k 10 5k ON/OFF VCC 7 5 0.1µF 3 18 9 562 OUTPUT 562 INPUT RS562 LINE PINS PROTECTED TO ±10kV 562 INPUT 16 1 DRIVER DISABLE 6 1385 F05 LTC1385 U PACKAGE DESCRIPTION Dimensions in inches (millimeters) unless otherwise noted. G Package 20-Lead SSOP 0.278 – 0.289* (7.07 – 7.33) 20 19 18 17 16 15 14 13 12 11 0.301 – 0.311 (7.65 – 7.90) 0.045 (1.14) 1 2 3 4 5 6 7 8 9 10 0.045 (1.14) 0.205 – 0.212* (5.20 – 5.38) 0.068 – 0.078 (1.73 – 1.99) 0° – 8° 0.005 – 0.009 (0.13 – 0.22) 0.0256 (0.65) BSC 0.022 – 0.037 (0.55 – 0.95) 0.002 – 0.008 (0.05 – 0.21) 0.010 – 0.015 (0.25 – 0.38) *THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.006 INCH (0.15mm). 20SSOP 0294 N Package 18-Lead Plastic DIP 0.905 (22.860) MAX 18 17 16 15 14 13 12 11 10 1 2 3 4 5 6 7 8 9 0.260 ± 0.010 (6.604 ± 0.254) 0.300 – 0.325 (7.620 – 8.255) 0.009 – 0.015 (0.229 – 0.381) ( +0.025 0.325 –0.015 8.255 +0.635 –0.381 ) 0.130 ± 0.005 (3.302 ± 0.127) 0.045 – 0.065 (1.143 – 1.651) 0.015 (0.381) MIN 0.065 (1.651) TYP 0.125 (3.175) MIN 0.045 ± 0.015 (1.143 ± 0.381) 0.100 ± 0.010 (2.540 ± 0.254) 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. 0.018 ± 0.003 (0.457 ± 0.076) N18 0392 7 LTC1385 U PACKAGE DESCRIPTION Dimensions in inches (millimeters) unless otherwise noted. S Package 18-Lead Plastic SOL 0.447 – 0.463 (11.354 – 11.760) (NOTE 2) 18 17 16 15 14 13 12 11 10 0.394 – 0.419 (10.007 – 10.643) SEE NOTE 0.005 (0.127) RAD MIN 1 0.291 – 0.299 (7.391 – 7.595) (NOTE 2) 0.010 – 0.029 × 45° (0.254 – 0.737) 2 3 0.093 – 0.104 (2.362 – 2.642) 4 5 6 7 8 9 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. 2. THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.006 INCH (0.15mm). 8 Linear Technology Corporation SOL18 0392 LT/GP 0594 10K • PRINTED IN USA 1630 McCarthy Blvd., Milpitas, CA 95035-7487 (408) 432-1900 ● FAX: (408) 434-0507 ● TELEX: 499-3977 LINEAR TECHNOLOGY CORPORATION 1994