LTC3520 Datasheet | Linear Technology

Synchronous 1A Buck-Boost and 600m A Buck Converters Features n Dual High Efficiency DC/DC Converters: Buck-Boost (VOUT: 2.2V to 5.25V, IOUT = 1A at VOUT = 3.3V, VIN ≥ 3V) Buck (VOUT: 0.8V to VIN, IOUT = 600m A) n 2.2V to 5.5V Input Voltage Range n Pin-Selectable Burst Mode® Operation n Unmitted Gain Block for LDO Controller, Battery Good Indication or Sequencing n Programmable 100k Hz to 2MHz Switching Frequency n 55μA Total Quiescent Current for Both Converters in Burst Mode Operation n Thermal and Overcurrent Protection n <1μA Quiescent Current in Shutdown n 24-Lead 4mm × 4mm QFN Package APPLICATIONS n Portable Media Players n Digital Cameras n Handheld PCs, PDAs n GPS Receivers L, LT, LTC, LTM, Linear Technology, the Linear logo and Burst Mode are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents, including 5481178, 6166527, 6304066, 6404251, 6580258. DESCRIPTION The LTC®3520 bines 1A buck-boost and 600m A synchronous buck DC/DC converters in a tiny 4mm × 4mm package. A programmable switching frequency allows the efficiency to be optimized while minimizing the solution footprint. Both converters feature soft-start and current limit protection. The unmitted gain block can be configured as an LDO or utilized as a battery-good parator. The buck converter is current mode controlled with internal synchronous rectification to improve efficiency. Pin-selectable Burst Mode operation can be enabled to improve light load efficiency, or the buck converter can be operated in low noise PWM mode for sensitive applications. The buck-boost converter provides continuous conduction operation to maximize efficiency and minimize noise. At light loads, use of Burst Mode operation will improve efficiency. The LTC3520 provides a <1μA shutdown mode and overtemperature shutdown on both converters. The LTC3520 is available in a low profile (0.75mm) 24-lead 4mm × 4mm QFN...