LT1331

LT1331_15 LINER | Alldatasheet

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Transceiver with One Receiver Active in Shutdown SFEATURE D UESCRIPTIO The LT 1331 is a 3-driver, 5-receiver RS232 transceiver designed for 3V and mixed 3V/5V systems. Receivers operate from 3V logic supply VL, while the onboard charge pump and drivers operate from 5V or 3V supply VCC. The transceiver has two shutdown modes. One mode disables the drivers and the charge pump, the other shuts down all circuitry except for one low power receiver which can be used for ring detection. The V CC supply may be shut down while in ring detection mode. While shut down, the drivers and receivers assume high impedance output states. The LT1331 is fully compliant with all EIA-RS232 specifi- cations when V CC = 5V. If VCC = 3V, output drive levels are compatible with all known interface circuits. Special bipo- lar construction techniques protect the drivers and receiv- ers beyond the fault conditions stipulated for RS232. The RS232 I/O pins are resilient to multiple ±10kV ESD strikes. An advanced driver output stage operates up to 120kbaud while driving heavy capacitive loads. n RS232 Compatible 3V Operation n 3V Logic Interface n ESD Protection Over ±10kV n 120kbaud Operation for RL = 3k, CL = 2500pF n 250kbaud Operation for RL = 3k, CL = 1000pF n One Low Power Receiver Remains Active While in Shutdown n 60µA Supply Current in Shutdown n Low Power Driver Disable Mode n Uses Small Capacitors: 0.1µF, 0.2µF n CMOS Comparable Low Power: 60mW n Easy PC Layout: Flowthrough Architecture n Rugged Bipolar Design n Outputs Assume a High Impedance State When Off or Powered Down n Notebook Computers n Palmtop Computers USA OPPLICATI , LTC and LT are registered trademarks of Linear Technology Corporation. R

1331 TA02

CL = 50pF DRIVER OUTPUT RL = 3k CL = 2500pF INPUT UA OPPLICATITYPICAL 3.3V Operation DRIVER 1 IN RX1 OUT DRIVER 2 IN RX2 OUT RX3 OUT RX4 OUT DRIVER 3 IN 0.1µF 2 × 0.1µF 2 × 0.1µF 0.1µF GND DRIVER DISABLE NC TO LINE TO LOGIC V –

1331 TA01

RX5 OUT (LOW-Q) RING DETECT IN µCONTROLLER OR µPROCESSOR SHUTDOWN CONTROL OUT LT1331 VCC = 3.3V DRIVER 1 OUT RX1 IN DRIVER 2 OUT RX2 IN RX3 IN RX4 IN DRIVER 3 OUT RX5 IN (LOW-Q) ON/OFF 3.3V V L

A UGWA WU WARBSOLUTEX I T I S WU UPACKAGE/ORDER I FOR ATIO ORDER PART NUMBER LT1331CG LT1331CNW LT1331CSW V 5V/3V VCC C1+ C1– DRIVER 1 OUT RX1 IN DRIVER 2 OUT RX2 IN RX3 IN RX4 IN DRIVER 3 OUT ON/OFF 3.3V V L V C2– C2+ DRIVER 1 IN RX1 OUT DRIVER 2 IN RX2 OUT RX3 OUT RX4 OUT DRIVER 3 IN GND NC NW PACKAGE 28-LEAD PDIP TOP VIEW SW PACKAGE 28-LEAD PLASTIC SO G PACKAGE 28-LEAD SSOP RX5 IN (LOW-Q) RX5 OUT (LOW-Q) DRIVER DISABLE Consult factory for Industrial and Military grade parts. TJMAX = 125°C, θJA = 96°C/ W (G) TJMAX = 125°C, θJA = 56°C/ W (NW) TJMAX = 125°C, θJA = 85°C/ W (SW) PARAMETER CONDITIONS MIN TYP MAX UNITS Power Supply Generator V+ Output V CC = 5V 8.6 V VCC = 3.3V 5.5 V V– Output V CC = 5V – 7.0 V VCC = 3.3V – 4.8 V Supply Current (VCC)V CC = 5V (Note 3) l 12 17 mA VCC = 3.3V l 12 17 mA Supply Current (VL) (Note 4) l 35 m A Supply Current When OFF (VCC) Shutdown (Note 5) l 25 0 µA Driver Disable 0.1 1 mA Supply Current When OFF (VL) Shutdown (Note 5) l 60 100 µA Driver Disable 3 5 mA Supply Rise Time, Shutdown to Turn-On C1 = C2 = 0.2 µF, C+ = C– = 0.1µF 0.2 ms ON/OFF Pin Thresholds Input Low Level (Device Shut Down) l 1.4 0.8 V Input High Level (Device Enabled) l 2.4 1.4 V ON/OFF Pin Current 0V ≤ VON/OFF ≤ 5V l –15 80 µA DRIVER DISABLE Pin Thresholds Input Low Level (Drivers Enabled) l 1.4 0.8 V Input High Level (Drivers Disabled) l 2.4 1.4 V DRIVER DISABLE Pin Current 0V ≤ VDRIVER DISABLE ≤ 5V l –10 500 µA Oscillator Frequency 130 kHz ELECTRICAL C CHARA TERISTICS (Note 2) (Note 1) Input Voltage CC + 0.3V Output Voltage L + 0.3V Short Circuit Duration

ELECTRICAL C CHARA TERISTICS The l denotes specifications which apply over the full operating temperature range (0°C ≤ TA ≤ 70°C for commercial grade). Note 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Note 2: Testing done at VCC = 5V, VL = 3.3V, and VON/OFF = 3V, unless otherwise stated. Note 3: Supply current is measured as the average over several charge pump cycles. C+ = 1µF, C– = 0.1µF, C1 = C2 = 0.2µF. All outputs are open with all driver inputs tied high. Note 4: VL supply current is measured with all receiver outputs high. Note 5: Supply current and leakage current measurements in shutdown are performed with VON/OFF ≤ 0.1V. Supply current measurements using driver disable are performed with VDRIVER DISABLE ≥ 3V. Note 6: For driver delay measurements, RL = 3k and CL = 51pF. Trigger points are set between the driver’s input logic threshold and the output transition to the zero crossing (t HL = 1.4V to 0V and tLH = 1.4V to 0V). Note 7: For receiver delay measurements, CL = 51pF. Trigger points are set between the receiver’s input logic threshold and the output transition to standard TTL/CMOS logic threshold (t HL = 1.3V to 2.0V and tLH = 1.7V to 0.8V). Note 8: Data rate operation guaranteed by slew rate, short-circuit current and propagation delay tests. PARAMETER CONDITIONS MIN TYP MAX UNITS Any Driver Output Voltage Swing, Positive V CC = 5V, RL = 3k l 5.0 6.5 V VCC = 3.3V, RL = 3k 3.7 4.0 V Output Voltage Swing, Negative V CC = 5V, RL = 3k l –6.0 –5.0 V VCC = 3.3V, RL = 3k – 3.3 – 2.7 V Logic Input Voltage Level Input Low Level (V OUT = High) l 1.4 0.8 V Input High Level (VOUT = Low) l 2.0 1.4 V Logic Input Current 0.8V ≤ VIN ≤ 2V l 52 0 µA Output Short-Circuit Current V OUT = 0V ± 91 7 m A Output Leakage Current Shutdown V OUT = ±30V (Note 5) l 10 100 µA Data Rate (Note 8) R L = 3k, CL = 2500pF 120 kBaud RL = 3k, CL = 1000pF 250 kBaud Slew Rate R L = 3k, CL = 51pF 15 30 V/ µs RL = 3k, CL = 2500pF 6 V/ µs Propagation Delay Output Transition t HL High to Low (Note 6) 0.6 1.3 µs Output Transition tLH Low to High 0.5 1.3 µs Any Receiver Input Voltage Thresholds Input Low Threshold (V OUT = High) l 0.8 1.3 V Input High Threshold (VOUT = Low) l 1.7 2.4 V Hysteresis l 0.1 0.4 1.0 V Input Resistance V IN = ±10V 3 5 7 k Ω Receivers 1 Through 4 Output Voltage Output Low, I OUT = –1.6mA l 0.2 0.4 V Output High, IOUT = 160µA (VL = 3.3V) l 2.0 2.4 V Output Short-Circuit Current Sinking Current, V OUT = VCC –2 0 –1 0 m A Sourcing Current, VOUT = 0V 10 20 mA Propagation Delay Output Transition t HL High to Low (Note 7) 250 600 ns Output Transition tLH Low to High 350 600 ns Output Leakage Current Shutdown (Note 5) 0 ≤ VOUT ≤ VCC l 11 0 µA Receiver 5 (Low Q-Current RX) Output Voltage Output Low, I OUT = –500 µA l 0.2 0.4 V Output High, IOUT = 160µA (VL = 3V) l 2.0 2.4 V Output Short-Circuit Current Sinking Current, V OUT = VCC –4 –2 m A Sourcing Current, VOUT = 0V 2 4 mA Propagation Delay Output Transition t HL High to Low (Note 7) 1 3 µs Output Transition tLH Low to High 1 3 µs

CCHARA TERISTICSUWATYPICALP E RFOR CE Driver Short-Circuit Current Supply Current vs Data Rate Driver Output VoltageDriver Output Voltage Receiver Input Thresholds Receiver Short-Circuit Current Slew Rate vs Load Capacitance TEMPERATURE (°C) –55 SHORT-CIRCUIT CURRENT (mA) 25 75

1331 G01

–25 0 50 100 125 ISC+ ISC– VCC = 5V TEMPERATURE (°C) –55 DRIVER OUTPUT VOLTAGE (V) 25 75

1331 G02

–25 0 50 100 125 VCC = 3.3V VCC = 5V RL = 3k

3 DRIVERS

Driver Leakage in Shutdown Slew Rate vs Load Capacitance TEMPERATURE (°C) –55

0.50 THRESHOLD VOLTAGE (V)

0.75 1.25 1.50 1.75 3.00 2.25 0 50 75

1331 G08

1.00 2.50 2.75 2.00 –25 25 100 125 INPUT HIGH INPUT LOW VL = 3.3V DATA RATE (kBAUD) SUPPLY CURRENT (mA) 25 50 75 100 125 150

1131 G07

1 DRIVER

VCC = 5V VCC = 3.3V VCC = 5V VCC = 3.3V RL = 3k CL = 2500pF TEMPERATURE (°C) –55 SHORT-CIRCUIT CURRENT (mA) 0 50 75

1331 G09

–25 25 100 125 ISC+ ISC– VL = 3.3V TEMPERATURE (°C) –55 DRIVER OUTPUT VOLTAGE (V) 25 75

1331 G03

–25 0 50 100 125 VCC = 3.3V VCC = 5V RL = 3k LOAD CAPACITANCE (nF) SLEW RATE (V/µs)

1331 G06

+SLEW –SLEW VCC = 3.3V LOAD CAPACITANCE (nF) SLEW RATE (V/µs)

1331 G05

+SLEW –SLEW VCC = 5V TEMPERATURE (°C) 0.1 LEAKAGE CURRENT (µA) 100

1331 G04

–55 0 50 75–25 25 100 125 VOUT = –30V VOUT = 30V

ON/OFF (Pin 13): A TTL/CMOS Compatible Operating Mode Control. A logic low puts the device in the shutdown mode. All drivers and four of the receivers go to a high impedance state, and the VCC supply may be turned off. A logic high fully enables the transceiver. VL (Pin 14): Power Supply for Receivers. This pin should be powered to the same voltage as the logic circuits connected to the receiver outputs, either 5V or 3V. The V L pin should be decoupled with a 0.1µF ceramic capacitor. DRIVER DISABLE (Pin 16): A logic high shuts down the charge pump, placing all drivers in a high impedance state. All receivers remain active. Floating the pin, or driving it to a logic low, fully enables the transceiver. A low voltage on the ON/OFF pin supersedes the state of the driver disable control. GND (Pin 17): Ground. LOW-Q RX OUT (Pin 18): Low Power Receiver Output. This pin produces the same output levels as standard receivers, with slightly decreased speed and short-circuit current. DRIVER IN (Pins 19, 23, 25): RS232 Driver Inputs. Inputs are TTL/CMOS compatible. Tie unused inputs to V CC. RX OUT (Pins 20, 21, 22, 24): Receiver Outputs. RX1 through RX4 outputs are in a high impedance state when in shutdown mode to allow data line sharing. Outputs, including LOW-Q RX OUT, are fully short-circuit pro- tected to ground, V CC, or VL. Output voltage levels are determined by the choice of power supply VL. V– (Pin 28): Negative Supply Output. V – ≅ –(2V CC – 2.5V). This pin requires an external charge storage capacitor, chosen to minimize ripple on V –. A minimum value of 0.1µF is recommended. V+ (Pin 1): Positive Supply Output. V+ ≅ 2VCC – 1.5V. This pin requires an external capacitor for charge storage, chosen to minimize ripple to acceptable levels. A mini- mum size of 0.1µF is recommended. VCC (Pin 2): Power Supply for Charge Pump and Drivers. Proper circuit operation is insured for V CC = 3V to 6V. VCC = 5V operation gives full RS232 compliant perfor- mance, 3V operation results in lower driver output ampli- tude. The V CC pin should be decoupled with a 0.1 µF ceramic capacitor. C1+, C1–, C2+, C2– (Pins 3, 4, 26, 27): These pins require two external capacitors C ≥ 0.2µF. 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 . Low ESR tantalum capacitors work well in this application, small value ceramic capacitors may also be used with minimal reduction in charge pump compliance. DRIVER OUT (Pins 5, 7, 11): RS232 Driver Outputs. Outputs are in a high impedance state when in shutdown, driver disable, or VCC = 0V. Outputs are fully short-circuit protected from V – + 30V to V + – 30V. Although the outputs are protected, short circuits on one output can load the power supply generator and may disrupt the signal levels of the other outputs. The driver outputs are protected against ESD to ±10kV for human body model discharges. Output levels of –3.3V to 4V are achieved when the circuit is operated with V CC = 3.3V. RX IN (Pins 6, 8, 9, 10): Receiver Inputs with 0.4V of Hysteresis for Noise Immunity. These pins accept RS232 level signals ( ±30V) into a protected 5k terminating resistor. The receiver inputs are protected against ESD to ±10kV for human body model discharges. LOW-Q RX IN (Pin 12): Low Power Receiver Input. This receiver remains active in shutdown mode, consuming only 60µA from supply V L. This receiver has the same input and protection characteristics as receivers RX1 through RX4.

consumption based upon applications needs. tion can be used to wake up the system for full operation. L and less than 100µA from VCC. may be driven by the LT1331. least –2.7V to 3.7V, with typical swing being –3.3V to 4V. Table 1. Commonly Used RS232 Interface Circuit Receiver Thresholds

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 represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights. ESD PROTECTIOU ESD Test CircuitThe RS232 line inputs of the LT1331 have on-chip protec- tion from ESD transients up to ±10kV. The protection structures act to divert the static discharge safely to system ground. In order for the ESD protection to function effectively, the power supply and ground pins of the LT1331 must be connected to ground through low imped- ances. The power supply decoupling capacitors and charge pump storage capacitors provide this low impedance in normal application of the circuit. The only constraint is that low ESR capacitors must be used for bypassing and charge storage. ESD testing must be done with pins V CC, VL, V+, V– and GND shorted to ground or connected with low ESR capacitors. DRIVER 1 IN RX1 OUT DRIVER 2 IN RX2 OUT RX3 OUT RX4 OUT DRIVER 3 IN RX5 OUT (LOW-Q) 0.1µF 0.2µF 0.2µF 0.1µF GND DRIVER DISABLE NC RS232 LINE PINS PROTECTED TO –10kV V – LT1331 DRIVER 1 OUT RX1 IN DRIVER 2 OUT RX2 IN RX3 IN RX4 IN DRIVER 3 OUT RX5 IN (LOW-Q) ON/OFF 0.1µF

1331 ESD TC

0.1µF 3.3V 5V VCC PACKAGE DESCRIPTIOU Dimensions in inches (millimeters) unless otherwise noted. N28 1197 0.009 – 0.015 (0.229 – 0.381) 0.625 +0.035 –0.015 +0.889 –0.38115.87 () 0.600 – 0.625 (15.240 – 15.875) 0.505 – 0.560* (12.827 – 14.224) 1.455* (36.957) MAX 12 3 4 5 6 7 8 9 10 27 1920212224 23252628 11 12 13 14 15161718 0.070 (1.778) TYP0.015 (0.381) MIN 0.125 (3.175) MIN 0.150 – 0.005 (3.810 – 0.127) 0.018 – 0.003 (0.457 – 0.076) 0.035 – 0.080 (0.889 – 2.032) 0.100 – 0.010 (2.540 – 0.254) 0.045 – 0.065 (1.143 – 1.651) *THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.010 INCH (0.254mm) 28-Lead PDIP (Wide 0.600) (LTC DWG # 05-08-1520) G Package 28-Lead Plastic SSOP (0.209) (LTC DWG # 05-08-1640) G28 SSOP 0694 0.301 – 0.311 (7.65 – 7.90) 1234 5 6 7 8 9 10 11 12 14 13 0.397 – 0.407* (10.07 – 10.33) 2526 22 21 20 19 18 17 16 15232427280.068 – 0.078 (1.73 – 1.99) 0.002 – 0.008 (0.05 – 0.21) 0.0256 (0.65) BSC 0.010 – 0.015 (0.25 – 0.38) 0.005 – 0.009 (0.13 – 0.22) 0° – 8° 0.022 – 0.037 (0.55 – 0.95) 0.205 – 0.212** (5.20 – 5.38) DIMENSIONS DO NOT INCLUDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE DIMENSIONS DO NOT INCLUDE INTERLEAD FLASH. INTERLEAD FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE

Dimensions in inches (millimeters) unless otherwise noted.  LINEAR TECHNOLOGY CORPORA TION 1993 1331fa LT/TP 0998 REV A 2K • PRINTED IN USA 28-Lead Plastic Small Outline (Wide 0.300) (LTC DWG # 05-08-1620) S28 (WIDE) 0996 0.037 – 0.045 (0.940 – 1.143) 0.004 – 0.012 (0.102 – 0.305) 0.093 – 0.104 (2.362 – 2.642) 0.050 (1.270) TYP 0.014 – 0.019 (0.356 – 0.482) TYP NOTE 1 0.697 – 0.712* (17.70 – 18.08) 1 23 4 5 6 78 0.394 – 0.419 (10.007 – 10.643) 91 0 2526 11 12 22 21 20 19 18 17 16 152324 1413 2728 0° – 8° TYP NOTE 1 0.009 – 0.013 (0.229 – 0.330) 0.016 – 0.050 (0.406 – 1.270) 0.291 – 0.299** (7.391 – 7.595) × 45°0.010 – 0.029 (0.254 – 0.737) 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 UA OPPLICATITYPICAL Mixed 5V/3V Supply Operation INPUT DRIVER OUTPUT RL = 3k CL = 2500pF RECEIVER OUTPUT CL = 50pF

1331 TA04

0.1µF 2 × 0.1µF 2 × 0.1µF 0.1µF GND DRIVER DISABLE NC TO LINE TO LOGIC V –

1331 TA03

RX5 OUT (LOW-Q) LT1331 VCC = 5V DRIVER 1 OUT RX1 IN DRIVER 2 OUT RX2 IN RX3 IN RX4 IN DRIVER 3 OUT RX5 IN (LOW-Q) ON/OFF V L = 3.3V PART NUMBER DESCRIPTION COMMENTS LT1130A/LT1140A 5V RS232 Transceivers with Small Capacitors 10kV ESD LT1137A 3-DR/5-RX RS232 Transceiver 15kV ESD LTC1349 5V Low Power, 3-DR/5-RX RS232 Transceiver 2 RXs Active in Shutdown LTC1385 3.3V Low Power EIA/TIA-562 Transceiver LT1780/LT1781 2-DR/2-RX RS232 Transceivers 15kV ESD RELATED PARTS Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 l FAX: (408) 434-0507 l www.linear-tech.com