The LTC3520EUF combines 1A buck-boost and 600mA synchronous buck DC/DC converters in a tiny 4mm x 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 uncommitted gain block can be configured as an LDO or utilized as a battery-good comparator.
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 LTC3520EUF provides a <1µA shutdown mode and over- temperature shutdown on both converters. The LTC3520EUF is available in a low profile (0.75mm) 24-lead 4mm x 4mm QFN package.
Feature
- 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 = 600mA)
- 2.2V to 5.5V Input Voltage Range
- Pin-Selectable Burst Mode® Operation
- Uncommitted Gain Block for LDO Controller, Battery Good Indication or Sequencing
- Programmable 100kHz to 2MHz Switching Frequency
- 55μA Total Quiescent Current for Both Converters in Burst Mode Operation
- Thermal and Overcurrent Protection
- <1μA Quiescent Current in Shutdown
- 24-Lead 4mm × 4mm QFN Package
Applications
- Portable Media Players
- Digital Cameras
- Handheld PCs, PDAs
- GPS Receivers
(Picture: Pinout)
