FEATURES DESCRIPTIO APPLICATIO S TYPICAL APPLICATIO. LTC1349 5V Low Power RS232 3-Driver/5-Receiver Transceiver with 2 Receivers Active in Shutdown

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1 V Low Power RS3 3-Driver/-Receiver Transceiver with Receivers Active in Shutdown FEATRES Low Supply Current: 3µA Two Receivers Kept Alive in Shutdown ESD Protection Over ±1kV Operates from a Single V Supply ses Small Capacitors:.1µF Operates to 1k Baud Three-State Outputs Are High Impedance When Off Output Overvoltage Does Not Force Current Back into Supplies RS3 I/O Lines Can Be Forced to ±V Without Damage Pin Compatible with LT1137A and LT137 Flowthrough Architecture APPLICATIO S Notebook Computers Palmtop Computers DESCRIPTIO The LTC 139 is a 3-driver/-receiver RS3 transceiver with very low supply current. In the no load condition, the supply current is only 3µA. The charge pump only requires four.1µf capacitors. In Shutdown mode, two receivers are kept alive and the supply current is 3µA. All RS3 outputs assume a high impedance state in Shutdown and with the power off. The LTC139 is fully compliant with all data rate and overvoltage RS3 specifications. The transceiver can operate up to 1k baud with a pf, 3kΩ load. Both driver outputs and receiver inputs can be forced to ±V without damage, and can survive multiple ±1kV ESD strikes., LTC and LT are registered trademarks of Linear Technology Corporation. TYPICAL APPLICATIO 3-Drivers/-Receivers with Shutdown Quiescent and Shutdown Supply Current vs Temperature C1.1µF C.1µF V + 1 OT RX1 IN OT RX IN RX3 IN RX IN 3 OT RX IN ON/OFF LTC V C3.1µF 1 IN RX1 OT IN RX OT RX3 OT RX OT 3 IN RX OT GND C.1µF LTC139 TA1 QIESCENT CRRENT (µa) 1 1 QIESCENT CRRENT SHTDOWN CRRENT 1 TEMPERATRE ( C) TEST CONDITION: = V, ALL INPTS TIED TO. 3 1 LTC139 TA SHTDOWN CRRENT (µa) 1

2 ABSOLTE AXI RATI GS W W W Supply Voltage ( )... V Input Voltage Driver....3V to +.3V Receiver... V to V On/Off Pin....3V to +.3V Output Voltage Driver... V to V Receiver....3V to +.3V Short Circuit Duration V sec V... 3 sec Driver Output... Indefinite Receiver Output... Indefinite Operating Temperature Range Commercial (LTC139C)... C to 7 C Industrial (LTC139I)... C to C Storage Temperature Range... C to C Lead Temperature (Soldering, 1 sec)... 3 C W PACKAGE/ORDER I FOR ATIO V + 1 C1 + 3 C1 DR1 OT RX1 IN DR OT 7 RX IN RX3 IN 9 RX IN 1 DR3 OT 11 RX IN 1 ON/OFF 13 1 G PACKAGE -LEAD SSOP TOP VIEW SW PACKAGE -LEAD PLASTIC SO V 7 C+ C DR1 IN RX1 OT 3 DR IN RX OT 1 RX3 OT RX OT 19 DR3 IN 1 RX OT 17 GND 1 NW PACKAGE -LEAD PDIP T JMAX = 1 C, θ JA = 9 C/W (G) T JMAX = 1 C, θ JA = C/W (NW) T JMAX = 1 C, θ JA = C/W (SW) ORDER PART NMBER LTC139CG LTC139CNW LTC139CSW LTC139IG LTC139INW LTC139ISW 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. = V, C1 = C = C3 = C =.1µF, unless noted. PARAMETER CONDITIONS MIN TYP MAX NITS Any Driver Output Voltage Swing 3k to GND Positive. 7. V Negative.. V Logic Input Voltage Level Input Low Level (V OT = High) 1.. V Input High Level (V OT = Low). 1. V Logic Input Current V IN = V µa V IN = V µa Output Short-Circuit Current V OT = V ±9 ±1 ma Output Leakage Current Shutdown, V OT = ±V (Note 3) ±1 ± µa Any Receiver Input Voltage Thresholds Input Low Threshold. 1.3 V Input High Threshold 1.7. V Hysteresis V Input Resistance 1V V IN 1V 3 7 kω Output Voltage Output Low, I OT = 1.mA ( = V).. V Output High, I OT = 1µA ( = V) 3.. V Output Short-Circuit Current Sinking Current, V OT = ma Output Leakage Current Shutdown, V OT (Note 3) 1 1 µa Power Supply Generator V + Output Voltage I OT = ma. V I OT = 1mA 7. V V Output Voltage I OT = ma. V I OT = 1mA 7. V Supply Rise Time Shutdown to Turn-On. ms

3 DC ELECTRICAL CHARACTERISTICS LTC139 The denotes specifications which apply over the full operating temperature range. = V, C1 = C = C3 = C =.1µF, unless noted. PARAMETER CONDITIONS MIN TYP MAX NITS Power Supply Supply Current No Load (All Drivers V IN = )(Note ), C T A 7 C.3. ma No Load (All Drivers V IN = V)(Note ), C T A 7 C. 1. ma No Load (All Drivers V IN = )(Note ), C T A C.3 1. ma No Load (All Drivers V IN = )(Note ), C T A C.3 1. ma No Load (All Drivers V IN = V)(Note ), C T A C. 1. ma Supply Leakage Current ( ) Shutdown (Note 3) 3 µa On/Off Threshold Low 1.. V On/Off Threshold High. 1. V AC CHARACTERISTICS The denotes specifications which apply over the full operating temperature range. = V, C1 = C = C3 = C =.1µF, unless noted. PARAMETER CONDITIONS MIN TYP MAX NITS Slew Rate, C L = 1pF 3 V/µs, C L = pf 3 V/µs Driver Propagation Delay t HLD (Figure 1) 3. µs (TTL to RS3) t LHD (Figure 1) 3. µs Receiver Propagation Delay t HLR (Figure ).3. µs (RS3 to TTL) t LHR (Figure ).. µs Note 1: Absolute Maximum Ratings are those values beyond which the life of the device may be impaired. Note : Supply current is measured with driver and receiver outputs unloaded. Note 3: Supply current and leakage current measurements in Shutdown are performed with V ON/OFF = V. TYPICAL PERFOR A CE CHARACTERISTICS W Driver Output Voltage Receiver Input Thresholds Supply Current vs Data Rate OTPT VOLTAGE (V) 1 OTPT HIGH = V =.V OTPT LOW =.V = V 1 TEMPERATRE ( C) THRESHOLD VOLTAGE (V) V TH V TL 1 TEMPERATRE ( C) SPPLY CRRENT (ma) = V C L = pf 3 S ACTIVE DATA RATE (k BAD) LTC139 TPC1 LTC139 TPC LTC139 TPC3 3

4 TYPICAL PERFOR A CE CHARACTERISTICS W Supply Current Driver Leakage in Shutdown Driver Short-Circuit Current 1 1 SPPLY CRRENT (ma) S LOADED 1 LOADED LEAKAGE CRRENT (µa) V OT = V V OT = V SHORT-CIRCIT CRRENT (ma) I SC + I SC TEMPERATRE ( C) TEMPERATRE ( C) 1 TEMPERATRE ( C) LTC139 TPC LTC139 TPC LTC139 TPC SHORT-CIRCIT CRRENT (ma) 3 Receiver Short-Circuit Current I SC + I SC OTPT C L = pf OTPT INPT Driver Output Waveforms LTC139 TPC RECEIVER OTPT C L = pf INPT Receiver Output Waveforms LTC139 TPC9 1 1 TEMPERATRE ( C) LTC139 TPC7 PI F CTIO S : V Input Supply Pin. Supply current is typically 3µA in the Shutdown mode. This pin should be decoupled with a.1µf ceramic capacitor. GND: Ground Pin. ON/OFF: TTL/CMOS Compatible Shutdown Pin. A logic low puts the device in Shutdown mode, with receivers and kept alive and the supply current equal to 3µA. All driver outputs and other receiver outputs are in high impedance state. This pin can not float. V + : Positive Supply Output (RS3 Drivers). V + 1V. This pin requires an external capacitor C =.1µF for charge storage. The capacitor may be tied to ground or V. 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 (RS3 Drivers). V 1.V. This pin requires an external capacitor C =.1µF for charge storage. C1 +, C1, C +, C : Commutating Capacitor Inputs. These pins require two external capacitors C =.1µF: one from C1 + to C1, and another from C + to C. To maintain charge pump efficiency, the capacitor s effective series resistance should be less than Ω.

5 PI F CTIO S IN: RS3 Driver Input Pins. Inputs are TTL/ CMOS compatible. Inputs should not be allowed to float. Tie unused inputs to. OT: Driver Outputs at RS3 Voltage Levels. Outputs are in a high impedance state when in Shutdown mode or = V. The driver outputs are protected against ESD to ±1kV for human body model discharges. RX IN: Receiver Inputs. These pins can be forced to ±V without damage. The receiver inputs are protected against ESD to ±1kV for human body model discharges. Each receiver provides.v of hysteresis for noise immunity. RX OT: Receiver Outputs with TTL/CMOS Voltage Levels. Receiver 1, and 3 outputs are in a high impedance state when in Shutdown mode to allow data line sharing. Receivers and are kept alive in Shutdown. W W SWITCHI G TI E WAVEFOR S INPT 1.V 1.V V OTPT t LHD V t HLD V V + V LTC139 F1 Figure 1. Driver Propagation Delay Timing RX INPT 1.7V 1.3V V RX OTPT t LHR.V t HLR.V V LTC139 F Figure. Receiver Propagation Delay Timing TEST CIRCITS Driver Timing Test Load Receiver Timing Test Load INPT OTPT 1pF 3k RX INPT RX RX OTPT 1pF LTC139 TA3 LTC139 TA

6 TEST CIRCITS ESD Test Circuit C1.1µF RS3 LINE PINS PROTECTED TO ±1kV C.1µF V + 1 OT RX1 IN OT RX IN RX3 IN RX IN 3 OT RX IN ON/OFF LTC V C3.1µF 1 IN RX1 OT IN RX OT RX3 OT RX OT 3 IN RX OT GND C.1µF LTC139 TC

7 PACKAGE DESCRIPTIO G Package -Lead Plastic SSOP (.3mm) (Reference LTC DWG # --1) 1. ± * (.39.13) (.91.33). ±.3. BSC RECOMMENDED SOLDER PAD LAYOT ** (.197.1). (.79).9. (.3.1)..9 (..37) NOTE: 1. CONTROLLING DIMENSION: MILLIMETERS MILLIMETERS. DIMENSIONS ARE IN (IHES) 3. DRAWING NOT TO SCALE * DIMENSIONS DO NOT ILDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED.mm (.") PER SIDE ** DIMENSIONS DO NOT ILDE INTERLEAD FLASH. INTERLEAD FLASH SHALL NOT EXCEED.mm (.1") PER SIDE. (.) BSC..3 (.9.). (.) G SSOP NW Package -Lead PDIP (Wide. Inch) (Reference LTC DWG # --) 1.7* (3.97) MAX * (1.7 1.) (..7). ±. (3.1 ±.17).. ( ).. (.3.31) ( ). (.31) MIN.1 (3.17) MIN NOTE: IHES 1. DIMENSIONS ARE MILLIMETERS *THESE DIMENSIONS DO NOT ILDE MOLD FLASH OR PROTRSIONS. MOLD FLASH OR PROTRSIONS SHALL NOT EXCEED.1 IH (.mm).3. (.9.3).1 (.) BSC.1 ±.3 (.7 ±.7) 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 (1.77) TYP NW 1 7

8 PACKAGE DESCRIPTIO SW Package -Lead Plastic Small Outline (Wide.3 Inch) (Reference LTC DWG # --1).3 ±. TYP N. BSC. ± ( ) NOTE MIN.3 ±. N NOTE ( ) 1 3 N/ N/ RECOMMENDED SOLDER PAD LAYOT. (.17) RAD MIN ( ) NOTE.1.9 (..737) TYP.93.1 (.3.) ( ) (1.7) (.9.33) NOTE 3 BSC (.3.) (. 1.7) TYP NOTE: IHES 1. DIMENSIONS IN (MILLIMETERS). DRAWING NOT TO SCALE 3. PIN 1 IDENT, NOTCH ON TOP AND CAVITIES ON THE BOTTOM OF PACKAGES ARE THE MANFACTRING OPTIONS. THE PART MAY BE SPPLIED WITH OR WITHOT ANY OF THE OPTIONS. THESE DIMENSIONS DO NOT ILDE MOLD FLASH OR PROTRSIONS. MOLD FLASH OR PROTRSIONS SHALL NOT EXCEED." (.mm)..1 (.1.3) S (WIDE) RELATED PARTS PART NMBER DESCRIPTION COMMENTS LT 1137A V, 3 Driver, Receiver RS3 Transceiver ±kv ESD per IEC 1- LTC V, 3 Driver, Receiver RS Transceiver 3µA Supply Current,.µA in Shutdown LTC1337 V, 3 Driver, Receiver RS3 Transceiver 3µA Supply Current, 1µA in Shutdown LTC13 3.3V to V, 3 Driver, Receiver RS3 Transceiver True RS3 on 3.3V, Receivers Active in Shutdown Linear Technology Corporation 13 McCarthy Blvd., Milpitas, CA () 3-19 FAX: () LW/TP 11 1K REV A PRINTED IN SA LINEAR TECHNOLOGY CORPORATION 1993