Linear Technology Intros LT3479 DC-DC Converter
Linear Technology Corp. (LTC, Milpitas, CA) announced its new LT3479, a current-mode, fixed-frequency, step-up dc-dc converter with an internal 3 A, 42 V switch. It operates from an input-voltage range of 2.5 V to 24 V, making it suitable for applications with input sources ranging from a single-cell, lithium-ion to a 20 V wall adapter.
Both inputs of the error amplifier are available to the user, permitting use as a boost converter or an inverter. The 42 V switch enables outputs as large as +40 V, and it can also drive two high-current white LEDs (in series) with current as high as 700 mA from a single lithium-ion cell. In addition, the switching frequency can be programmed, via a single resistor, between 300 kHz and 3.5 MHz, enabling the designer to minimize external component sizes and avoid "noise-critical" frequency bands in the system. A low-profile inductor and ceramic capacitors keep solution footprints compact while minimizing solution cost.
The LT3479's low VCESAT switch, 0.3 V at 2.5 A, delivers efficiencies of up to 89%. The device features a programmable soft-start function to limit inductor current during startup as well as inrush current protection to protect the LT3479 during shorts and line transients. The low-profile (0.75 mm), 14-pin, 4 mm x 3 mm, DFN-14 package provides thermal performance in a small footprint. The LT3479 is also available in a thermally enhanced, 16-pin TSSOP package.
Both the LT3479EDE in a 4 mm x 3 mm DFN-14 package and the LT3479EPE TSSOP-16E version are available from stock. Pricing for both package options starts at $3.00 each for 1,000-piece quantities.
