LTC1522 Datasheet | Linear Technology

LTC1522 Micropower, Regulated 5V Charge Pump DC/DC Converter Features s s s s s s s DESCRIPTION The LTC®1522 is a micropower charge pump DC/DC converter that produces a regulated 5V output from a 2.7V to 5V input supply. Extremely low supply current (6µA typical with no load, < 1µA in shutdown) and low external parts count (one 0.22µF flying capacitor and two 10µF capacitors at VIN and VOUT) make the LTC1522 ideally suited for small, light load battery-powered applications. Typical efficiency (VIN = 3V) exceeds 75% with load currents between 50µA and 20m A. Modulating the SHDN pin keeps the typical efficiency above 75% with load currents all the way down to 10µA. The LTC1522 has thermal shutdown and can survive a continuous short from VOUT to GND. In shutdown the load is disconnected from VIN. The part is available in 8-pin MSOP and SO packages. The LTC1522 is pin patible with the LTC1516 in applications where VIN ≥ 2.7V and IOUT ≤ 20m A. , LTC and LT are registered trademarks of Linear Technology Corporation. s s s s Ultralow Power: Typical Operating ICC = 6µA Short-Circuit/Thermal Protected Regulated 5V ± 4% Output Voltage 2.7V to 5V Input Range No Inductors Very Low ICC in Shutdown: < 1µA Output Current: 10m A (VIN ≥ 2.7V) 20m A (VIN ≥ 3V) Shutdown Disconnects Load from VIN Internal Oscillator: 700k Hz pact Application Circuit (< 0.1 in2) 8-Pin MSOP and SO Packages U APPLICATIONS s s s s s SIM Interface Supplies for GSM Cellular Telephones Li-Ion Battery Backup Supplies Local 3V to 5V Conversion Smart Card Readers PCMCIA Local 5V Supplies TYPICAL APPLICATION Regulated 5V Output from a 2.7V to 5V Input VIN 2.7V TO 5V 1 Efficiency vs Output Current 90 VIN = 3V + NC VIN VOUT C+ 0.22µF NC SHDN LTC1522 GND C- 8 7 6 5 10µF 2 3 ON/OFF EFFICIENCY (%) + 10µF 4 70 SHDN = 0V VOUT = 5V ± 4% IOUT = 0m A TO 10m A, VIN ≥ 2.7V IOUT = 0m A TO 20m A, VIN ≥ 3V 1522 TA01 50 0.01 LOW IQ MODE (SEE FIGURE 2) 0.1 1 10 OUTPUT CURRENT (m A) 1522...