Linear Tech’s 36V, 3.5A Step-Down DC-DC Converter Draws Quiescent Current of 75µA
Linear Technology Corp. announced the LT3680, a 3.5A, 36V step-down switching regulator with Burst Mode® operation to keep quiescent current under 75µA. The LT3680 operates within a VIN range of 3.6 to 36V, making it suitable for load dump and cold-crank conditions found in automotive applications. Its 4.6A internal switch can deliver up to 3.5A of continuous output current to voltages as low as 0.79V.
The LT3680’s Burst Mode operation offers ultra-low quiescent current, well suited for applications such as automotive or telecom systems, which demand always-on operation and optimum battery life. Switching frequency is user programmable from 250kHz to 2.4MHz, enabling the designer to optimize efficiency while avoiding critical noise-sensitive frequency bands. Its 3mm x 3mm DFN-10 package (or thermally enhanced MSOP-10E) and high switching frequency keep external inductors and capacitors small, providing a compact, thermally efficient footprint.
The LT3680 utilizes a high efficiency 4.6A, 95mΩ switch, with the necessary boost diode, oscillator, control and logic circuitry integrated into a single chip. Low ripple Burst Mode operation maintains high efficiency at low output currents while keeping output ripple below 15mVPK-PK. Special design techniques used in the LT3680 enable high efficiency over a wide input voltage range, and the devices’s current mode topology enables fast transient response and excellent loop stability. Other features include external synchronization (from 250kHz to 2MHz), a power good flag and soft-start capability.
Pricing for the LT3680EDD and LT3680EMSE starts at $4.15 and $4.25 each, respectively for 1,000-piece quantities. The LT3680IDD and LT3680IMSE are tested and guaranteed to operate from a -40 to 125°C operating junction temperature, priced at $4.98 and $5.10 each, respectively in 1,000-piece quantities. All versions are available from stock.
