LTC3388-1/LTC3388-3 20V High Efficiency Nanopower Step-Down Regulator FEATURESDESCRIPTION n 720nA Input IQ in Regulation (No Load), VIN = 4V The LTC®3388-1/LTC3388-3 are high efficiency step-down n 820nA Input IQ in Regulation (No Load), VIN = 20V DC/DC converters with internal high side and synchronous n 400nA Input IQ in UVLO power switches that draw only 720nA typical DC supply cur- n 2.7V to 20V Input Operating Range rent at no load while maintaining output voltage regulation. n Up to 50mA of Output Current Capable of supplying 50mA of load current, the LTC3388-1/ n Pin Selectable Output Voltages: LTC3388-3 also incorporate an accurate undervoltage n 1.2V, 1.5V, 1.8V, 2.5V (LTC3388-1) lockout (UVLO) feature to disable the converter and main- n 2.8V, 3.0V, 3.3V, 5.0V (LTC3388-3) tain a low quiescent current state when the input voltage n High Efficiency Hysteretic Synchronous falls below 2.3V. In regulation, the LTC3388-1/LTC3388-3 DC/DC Conversion enter a sleep state in which both input and output quies- n Standby Mode Disables Buck Switching cent currents are minimal. The buck converter turns on n Available in 10-Lead MSE and 3mm × 3mm and off as needed to maintain regulation. An additional DFN Packages standby mode disables buck switching while the output is in regulation for short duration loads requiring low ripple. APPLICATIONS Output voltages of 1.2V, 1.5V, 1.8V, 2.5V (LTC3388-1) n Keep Alive Power for Portable Products and 2.8V, 3.0V, 3.3V, 5.0V (LTC3388-3) are pin selectable. n Industrial Control Supplies The LTC3388-1/LTC3388-3 can operate with VIN up to 20V n Distributed Power Systems while the no load quiescent current remains below 1µA. n L, LT, LTC, LTM, Linear Technology, the Linear logo and Burst Mode are registered trademarks Battery-Operated Devices of Linear Technology Corporation. All other trademarks are the property of their respective owners. TYPICAL APPLICATION50mA Step-Down ConverterEfficiency vs Load Current 100 VOUT = 1.8V, L = 100µH 2.7V TO 20V VIN 90 1µF LTC3388-1/ 6V LTC3388-3 100µH 80 CAP SW VOUT 2.2µF 70 V 47µF 25V IN2 VOUT 6V 60 4.7µF EN PGOOD 6V 2 50 STBY D0, D1 OUTPUT VOLTAGE 40 GND SELECT EFFICIENCY (%) 30 338813 TA01a 20 VIN = 3.0V 10 VIN = 10V VIN = 20V 01µ 10µ 100µ 1m 10m LOAD CURRENT (A) 338813 TA01b 338813fa For more information www.linear.com/LTC3388 1 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Application Related Parts
