The LT3514’s switching frequency is user-programmable from 250kHz to 2.2MHz and is synchronizable throughout the range, enabling the designer to optimize efficiency while avoiding critical noise-sensitive frequency bands. The combination of its 28-lead 4mm x 5mm QFN package and high switching frequency keeps external inductors and capacitors small, providing a compact, thermally efficient footprint for multiple output applications.
The LT3514 utilizes one internal 3A switch and two 1.45A switches for the step-down conversion and a 220mA switch for the internal boost circuit, with the necessary oscillator, control and logic circuitry integrated into a single die. Special design techniques deliver efficiencies up to 88% over a wide input voltage range, and the LT3514’s current mode topology enables fast transient response and excellent loop stability. Anti-phase switching reduces input ripple and robust short-circuit protection enhances system reliability. Other features include output voltage tracking, programmable undervoltage lockout and a power good pin to indicate when all outputs are in regulation.
The LT3514 is available in thermally enhanced 4mm x 5mm QFN-28 and TSSOP-24 packages. The LT3514E is priced starting at $3.50 each for 1,000-piece quantities. The LT3514I is tested and guaranteed to operate from a -40°C to 125°C junction temperature range and is priced starting at $3.85 each for 1,000-piece quantities. Both versions are available from stock.