Buck-Boost Converter: LTC3114-1
The LTC3114-1is a synchronous, current-mode buck-boost converter that delivers up to 1A of continuous output current from a wide range of power sources, including single-cell Li-Ion, 24 V/28 V industrial rails and 40V automotive inputs. The LTC3114-1’s 2.2 V to 40 V input and 2.7V to 40 V output range provides a regulated output with inputs above, below or equal to the regulated output, maximizing power source flexibility and extending battery run time over step-down only solutions. The proprietary low noise buck-boost topology incorporated in the LTC3114-1 provides a continuous jitter-free transition between buck and boost modes, making it ideal for RF and other noise-sensitive applications.
The device’s selectable Automatic Burst Mode® operation lowers quiescent current to only 30µA, improving light load efficiency and further extending battery run time. The LTC3114-1 uses a constant 1.2 MHz switching frequency and features pin-programmable average output current and current monitor. Proprietary buck-boost PWM circuitry ensures low noise and high efficiency while minimizing the size of external components. The combination of tiny externals and a 3mm x 5mm DFN or TSSOP-16E package provides a compact solution footprint.
The LTC3114-1 incorporates four internal low RDS(ON) N-channel MOSFETs to deliver efficiencies of up to 96%. Automatic Burst Mode operation lowers quiescent current to only 30µA, improving light load efficiency and extending battery run time. For noise-sensitive applications, Burst Mode operation can be disabled. Furthermore, current-mode control improves line and load transient responses while keeping compensation simple. Additional features include internal soft-start and inrush current limit, undervoltage lockout, thermal overload protection, short-circuit protection and output disconnect.
LTC3114EDHC-1 is available in a 16-lead 3mm x 5mm DFN package and the LTC3114EFE-1 is in a thermally enhanced 16-lead TSSOP package. Pricing starts at $3.95 each for 1,000 piece quantities. Industrial grade versions, the LTC3114IDHC-1 and LTC3114IFE-1, are guaranteed to operate over the -40°C to 125°C operating junction temperature range, priced at $4.35 and $4.51 each, respectively, in 1,000-piece quantities. High temperature grade versions, the LTC3114HDHC-1 and LTC3114HFE-1, are guaranteed to operate over the -40°C to 150°C operating junction temperature range, priced at $4.60 and $4.76 each, respectively, in 1,000-piece quantities. Finally high reliability versions, the LTC3114MPDHC-1 and LTC3114MPFE-1, are guaranteed to operate over the -55°C to 150°C operating junction temperature range, priced starting at $11.73 each, in 1,000-piece quantities. All versions are available from stock. For more information, visit www.linear.com/product/LTC3114.