Linear Technology has announced the LT3690, a 36V input capable, synchronous step-down switching regulator which can deliver up to 4A of continuous output current at efficiencies of 93%. The device operates within a VIN range of 3.9 to 36V, and offers transient protection to 60V, making it suitable for load dump and cold-crank conditions found in automotive applications. The Burst Mode operation requires 70μA of quiescent current, suitable for applications such as automotive or telecomms systems, which demand always-on operation and optimum battery life. Switching frequency is user-programmable from 170kHz to 1.5MHz, enabling the designer to optimise efficiency while avoiding critical noise-sensitive frequency bands. The combination of its 4x6mm QFN-26 package and high switching frequency keeps external inductors and capacitors small, providing a thermally efficient footprint.It utilises a high efficiency 5.5A, 90mΩ high-side switch with the necessary boost diode, oscillator, control and logic circuitry integrated into a single chip. The 30mΩ internal synchronous power switch increases efficiency and eliminates the need for an external Schottky catch diode.
