LT1300 LINER

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n Up to 220mA Output Current at 5V from 2V Supply n Supply Voltage as Low as 1.8V n Up to 88% Efficiency n Small Inductor –10µH n 120µA Quiescent Current n Shutdown to 10µA n Programmable 3.3V or 5V Output n ILIM Pin Programs Peak Switch Current n Low VCESAT Switch: 170mV at 1A Typical n Uses Inexpensive Surface Mount Inductors n 8-Lead DIP or SOIC Package n Palmtop Computers n Portable Instruments n Bar-Code Scanners n DC/DC Converter Module Replacements n Battery Backup Supplies n Personal Digital Assistants n PCMCIA Cards The LT1300 is a micropower step-up DC/DC converter that utilizes Burst Mode™ operation. The device can deliver 5V or 3.3V from a two-cell battery input. It features program- mable 5V or 3.3V output via a logic-controlled input, no- load quiescent current of 120µA and a shutdown pin which reduces supply current to 10µA. The on-chip power switch has a low 170mV saturation voltage at a switch current of 1A, a four-fold reduction over prior designs. A 155kHz internal oscillator allows the use of extremely small sur- face mount inductors and capacitors. Operation is guaran- teed at 1.8V input. This allows more energy to be extracted from the battery increasing operating life. The I LIM pin can be used to program peak switch current with a single resistor allowing the use of less expensive and smaller inductors and capacitors in lighter load applications. The LT1300 is available in an 8-lead SOIC package, minimizing board space requirements. For a 5V/12V Selectable Out- put Converter see the LT1301. For increased output cur- rent see the LT1302. DESCRIPTIONUFEATURES TYPICAL APPLICATIONS N U Micropower High Efficiency 3.3/5V Step-Up DC/DC Converter APPLICATIONSU Two-Cell to 3.3V/5V Step-Up Converter 5V Output Efficiency L1 = COILCRAFT DO1608-103 OR SUMIDA CD54-100 C1 = AVX TPSD107M010R0100 OR SANYO OS-CON 16SA100M D1 = MBRS130LT3 OR 1N5817 100µF 5V/3.3V OUTPUT 10µH D1 100µF AA CELL SW ILIM PGND GND SENSE LT1300 SELECT LT1300 TA1 5V/3.3V SELECT SHDNSHUTDOWN N/C VIN LOAD CURRENT (mA) 10 100 500 LT1300 TA2 EFFICIENCY (%) 88 VIN = 4.0V VIN = 3.0V VIN = 2.5V VIN = 2.0V Burst Mode is a trademark of Linear Technology Corporation.

ABSOLUTE MAXIMUM RATINGSW WW U PACKAGE/ORDER INFORMATIONW UU I S8 PART MARKING TJMAX = 100°C, θJA = 150°C/ W 1300 LT1300CN8 LT1300CS8 Consult factory for Industrial grade parts. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS IQ Quiescent Current V SHDN = 0.5V, VSEL = 5V, VSENSE = 5.5V l 120 200 µA VSHDN = 1.8V l 71 5 µA VIN Input Voltage Range 1.8 V l 2.0 V VOUT Output Sense Voltage V SEL = 5V l 4.80 5.0 5.20 V VSEL = 0V l 3.15 3.3 3.45 V Output Referred V SEL = 5V (Note 1) l 22 50 mV Comparator Hysteresis V SEL = 0V (Note 1) l 14 35 mV Oscillator Frequency Current Limit not Asserted. See Test Circuit. 120 155 185 kHz Oscillator TC 0.2 %/ °C DC Maximum Duty Cycle 75 86 95 % tON Switch On Time Current Limit not Asserted. 5.6 µs Output Line Regulation 1.8V < V IN < 6V l 0.06 0.15 %/V VCESAT Switch Saturation Voltage I SW = 700mA l 130 200 mV Switch Leakage Current V SW = 5V, Switch Off l 0.1 10 µA Peak Switch Current I LIM Floating (See Typical Application) 0.75 1.0 1.25 A (Internal Trip Point) I LIM Grounded 0.4 A VSHDNH Shutdown Pin High l 1.8 V VSHDNL Shutdown Pin Low 0.5 V VSELH Select Pin High l 1.5 V VSELL Select Pin Low l 0.8 V ISHDN Shutdown Pin Bias Current V SHDN = 5V l 92 0 µA VSHDN = 2V l 3 µA VSHDN = 0V l 0.1 1 µA ISEL Select Pin Bias Current 0V < V SEL < 5V l 13 µA ELECTRICAL CHARACTERISTICSTA = 25°C, VIN = 2V unless otherwise noted. Note 1: Hysteresis specified is DC. Output ripple may be higher if output capacitance is insufficient or capacitor ESR is excessive. See applications section. The l denotes specifications which apply over the 0°C to 70°C temperature range. TOP VIEW GND SEL SHDN SENSE PGND SW V IN ILIM N8 PACKAGE 8-LEAD PLASTIC DIP S8 PACKAGE 8-LEAD PLASTIC SOIC

TYPICAL PERFORMANCE CHARACTERISTICS UW No-Load Battery Current Total Quiescent Current in Shutdown SWITCH CURRENT (A) 0 0.1 VCESAT (mV) 150 125 200 175 250 225 0.8 0.9 LT1300 G5 100 Maximum Output Current vs Input Voltage Maximum Output Current vs Input Voltage 200µs/DIV Transient Response VIN = 2V, VOUT = 5V Startup Response VCESAT vs ISW Efficiency Shutdown Pin Bias Current VOUT 100mV/DIV AC COUPLED VOUT 1V/DIV VSHDN 10V/DIV LT1300 G8 SHUTDOWN VOLTAGE (V) SHUTDOWN CURRENT (µA) 2 4 5 LT1300 G4 13 6 7 8 TA = 25°C LOAD CURRENT (mA) EFFICIENCY (%) 10 100 1000 LT1300 G1 VIN = 3V VIN = 2V VIN = 2.5V VOUT = 3.3V L = 10µH INPUT VOLTAGE (V) 1.4 INPUT CURRENT (µA) 150 145 160 155 170 165 3.02.8 LT1300 G2 140 135 130 125 120 VOUT = 5V VOUT = 3.3V INPUT VOLTAGE (V) ISHDN + IVIN + ISENSE (µA) LT1300 G3 2 4 6 1 3 5 7 INPUT VOLTAGE (V) 1.5 OUTPUT CURRENT (mA) 500 600 700 LT1300 G6 400 300 2 2.5 3.5 4.5 200 100 VOUT = 5V, ILIM FLOATING L = 22µH COILCRAFT DO3316-223 L = 10µH COILCRAFT DO1608-103 INPUT VOLTAGE (V) 1.5 LOAD CURRENT (mA) 100 300 400 500 2.5 3 3.5 900 LT1300 G7 200 600 700 800 L = 10µH VOUT = 3.3V ILIM FLOATING VOUT = 5V RLOAD = 20Ω LT1300 G9 500µs/DIV 200mAILOAD

Table 1. Recommended Inductors their closed design and inherent EMI/RFI superiority. Recommended inductors are listed in Table 1. increase. Suggested capacitor sources are listed in Table 2. Table 2. Recommended Capacitors used although efficiency will suffer substantially. possible. This keeps radiated noise to a minimum. Information furnished by Linear Technology Corporation is believed to be accurate and reliable. tation that the interconnection of its circuits as described herein will not infringe on existing patent rights.

Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7487 (408) 432-1900 l FAX: (408) 434-0507 l TELEX: 499-3977 1 2 3 4 0.150 – 0. (3.810 – 3. 8 7 6 5 0.189 – 0.197* (4.801 – 5.004) 0.228 – 0.244 0.406 – 1.270 0.010 – 0.020 0°– 8° TYP 0.008 – 0.010 (0.203 – 0.254) SO8 0294 0.053 – 0.069 (1.346 – 1.752) 0.014 – 0.019 (0.355 – 0.483) 0.004 – 0.010 (0.101 – 0.254) 0.050 (1.270) BSC *THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.006 INCH (0.15mm). 8-Lead Plastic S0IC TYPICAL APPLICATIONS N U  LINEAR TECHNOLOGY CORPORA TION 1 994 LT/GP 0394 10K • PRINTED IN USA PACKAGE DESCRIPTIONU Dimensions in inches (millimeters) unless otherwise noted. Four-Cell to 5V/3.3V Up-Down Converter 8-Lead Plastic DIP N8 0392 0.009 – 0.015 (0.229 – 0.381) 0.300 – 0.320 (7.620 – 8.128) 0.325 +0.025 –0.015 +0.635 –0.3818.255() 0.045 ± 0.015 (1.143 ± 0.381) 0.100 ± 0.010 (2.540 ± 0.254) 0.065 (1.651) TYP 0.045 – 0.065 (1.143 – 1.651) 0.130 ± 0.005 (3.302 ± 0.127) 0.020 (0.508) MIN 0.018 ± 0.003 (0.457 ± 0.076) 0.125 (3.175) MIN 12 3 4 87 6 5 0.250 ± 0.010 (6.350 ± 0.254) 0.400 (10.160) MAX 100µF 22µF 35V CONTRAST VOUT –4V TO –29V 12mA MAXIMUM FROM 1.8V SUPPLY (77% EFFICIENT) 20mA MAXIMUM FROM 3V SUPPLY (83% EFFICIENT) 2.2µF SW PWM IN 0% TO 100% CMOS DRIVE 0V TO 5V 150K 12K 12K 10 8 ILIM PGND GND SENSE LT1300 SELECT LT1300 TA6 1N5819 T1 = DALE LPE-5047-AO45 (605) 665-9301 SHDN SHUTDOWN N/C N/C VIN VIN 1.8V TO 6V 1N5817 2N4403 5V, 200mA L1* 10µH *SUMIDA CD54-100LC COILCRAFT DO3316-223 100µF 100µF 470Ω 0.1µF AA CELL SW ILIM PGNDGND SENSE LT1300 SELECT LT1300 TA5 SHDN NC SHUTDOWN VIN Step-Up Converter with Automatic Output Disconnect LCD Contrast Supply 1N5817 5V/3.3V 220mA 80% EFFICIENT L1* 27µH *L1, L2 = GOWANDA GA20-272K COILCRAFT DO3316-273K SUMIDA CD73-270K **C1, C2, C3 = SANYO OS-CON 16SA100M L2* 27µH C1 100µF C2 100µF C3** 100µF AA CELL SW ILIM PGNDGND SENSE LT1300 SELECT LT1300 TA3 5V/3.3V 2.5V ≤ VIN ≤ 8V SHDNSHUTDOWN N/C VIN