LTC1751/LTC1751-3.3/LTC1751-5 Micropower, Regulated Charge Pump DC/DC Converters FEATURES DESCRIPTIO n 5V Output Current: 100mA (V 3V) The LTC 1751 family are micropower charge pump DC/ IN n 3.3V Output Current: 80mA (V 2.5V) DC converters that produce a regulated output voltage at IN n Ultralow Power: 20m A Quiescent Current up to 100mA. The input voltage range is 2V to 5.5V. n Regulated Output Voltage: 3.3V 4%, 5V 4%, ADJ Extremely low operating current (20m A typical with no n No Inductors load) and low external parts count (one flying capacitor n Short-Circuit/Thermal Protection and two small bypass capacitors at V and V ) make IN OUT n V Range: 2V to 5.5V them ideally suited for small, battery-powered applica- IN n 800kHz Switching Frequency tions. n Very Low Shutdown Current: <2m A TM The LTC1751 family operate as Burst Mode switched n Shutdown Disconnects Load from V IN capacitor voltage doublers to achieve ultralow quiescent n PowerGood/Undervoltage Output current. They have thermal shutdown capability and can n Adjustable Soft-Start Time survive a continuous short circuit from V to GND. The OUT n Available in an 8-Pin MSOP Package PGOOD pin on the LTC1751-3.3 and LTC1751-5 indicates when the output voltage has reached its final value and if U the output has an undervoltage fault condition. The FB pin APPLICATIO S of the adjustable LTC1751 can be used to program the n Li-Ion Battery Backup Supplies desired output voltage or current. An optional soft-start n Local 3V and 5V Conversion capacitor may be used at the SS pin to prevent excessive n Smart Card Readers inrush current during start-up. n PCMCIA Local 5V Supplies The LTC1751 family is available in an 8-pin MSOP n White LED Backlighting package. , LTC and LT are registered trademarks of Linear Technology Corporation. Burst Mode is a trademark of Linear Technology Corporation. TYPICAL APPLICATIO Output Voltage vs Input Voltage 5.2 I = 50mA OUT C = 1F Regulated 5V Output from a 2.7V to 5.5V Input FLY C = 10F OUT 5.1 V IN 3 2 V OUT 2.7V V V T = 85C IN OUT 5V 4% A C2 R1 C1 TO 5.5V T = 25C I 100mA, V 3V A OUT IN 100k 10F 7 1 10F 5.0 I 50mA, V 2.7V OFF ON SHDN PGOOD PGOOD OUT IN LTC1751-5 8 6 + SS C T = 40C A C FLY 4.9 1F 4 5 GND C 1751 TA01 C = MURATA GRM39X5R105K6.3AJ FLY 4.8 C1, C2 = MURATA GRM40X5R106K6.3AJ 2.5 3.0 3.5 4.0 4.5 5.0 5.5 INPUT VOLTAGE (V) 1751 TA02 1 OUTPUT VOLTAGE (V) U ULTC1751/LTC1751-3.3/LTC1751-5 UUW ABSOLUTE AXI U RATI GS PACKAGE/ORDER I FOR ATIO (Note 1) V to GND.................................................. 0.3V to 6V ORDER PART IN NUMBER PGOOD, FB, V to GND ........................... 0.3V to 6V TOP VIEW OUT SS, SHDN to GND ........................ 0.3V to (V + 0.3V) FB/PGOOD* 1 8 SS IN LTC1751EMS8 V 2 7 SHDN OUT V Short-Circuit Duration ............................. Indefinite + OUT V 3 6 C LTC1751EMS8-3.3 IN GND 4 5 C I (Note 2)....................................................... 125mA LTC1751EMS8-5 OUT MS8 PACKAGE Operating Temperature Range (Note 3) .. 40 C to 85 C 8-LEAD PLASTIC MSOP MS8 PART MARKING Storage Temperature Range ................ 65 C to 150 C T = 150 C, q = 160 C/W JMAX JA LTKL Lead Temperature (Soldering, 10 sec)................. 300 C *PGOOD ON LTC1751-3.3/LTC1751-5 FB ON LTC1751 LTKN LTKP Consult factory for parts specified with wider operating temperature ranges. ELECTRICAL CHARACTERISTICS The l denotes specifications which apply over the full specified temperature range, otherwise specifications are at T = 25 C. C = 1m F, C = 10m F, C = 10m F unless otherwise noted. A FLY IN OUT SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS LTC1751-3.3 V Input Supply Voltage l 2 4.4 V IN V Output Voltage 2V V 4.4V, I 40mA l 3.17 3.3 3.43 V OUT IN OUT 2.5V V 4.4V, I 80mA l 3.17 3.3 3.43 V IN OUT I Operating Supply Current 2V V 4.4V, I = 0mA, SHDN = V l 18 40 m A CC IN OUT IN V Output Ripple V = 2.5V, I = 40mA 68 mV R IN OUT P-P h Efficiency V = 2V, I = 40mA 80 % IN OUT LTC1751-5 V Input Supply Voltage l 2.7 5.5 V IN V Output Voltage 2.7V V 5.5V, I 50mA l 4.8 5 5.2 V OUT IN OUT 3V V 5.5V, I 100mA l 4.8 5 5.2 V IN OUT I Operating Supply Current 2.7V V 5.5V, I = 0mA, SHDN = V l 20 50 m A CC IN OUT IN V Output Ripple V = 3V, I = 50mA 75 mV R IN OUT P-P h Efficiency V = 3V, I = 50mA 82 % IN OUT LTC1751 V Input Supply Voltage l 2 5.5 V IN I Operating Supply Current 2V V 5.5V, I = 0mA, SHDN = V (Note 4 ) l 16 40 m A CC IN OUT IN V FB Regulation Voltage 2V V 5.5V, I 20mA l 1.157 1.205 1.253 V FB IN OUT I FB Input Current V = 1.3V l 50 50 nA FB FB R Open-Loop Charge Pump Strength V = 2V, V = 3.3V (Note 5) l 8.5 20 W OUT IN OUT V = 2.7V, V = 5V (Note 5) l 6.0 12 W IN OUT 2 U WWW