Current-mode fixed-frequency SEPIC / boost DC-DC converter with 2A / 70V switch

Linear Technology has unveiled the LT8495, a new current-mode, fixed-frequency SEPIC / boost DC-DC converter with an internal 2A, 70V switch. A ultra-low quiescent current of only 9µA makes the device ideal for always-on automotive systems. Its integrated power-on reset (POR) and watchdog timer offer enhanced system reliability required in automotive and industrial applications. The LT8495 starts up from an input voltage range of 2.5V to 32V, and once running, it operates from inputs of 1V to 60V, making it suitable for applications with input sources ranging from a single-cell Li-Ion to automotive inputs. The LT8495 can be configured as either a boost, SEPIC or fly-back converter. Its switching frequency is programmable via a single resistor between 250kHz and 1.5MHz, minimizing external component sizes. The combination of a thermally enhanced TSSOP-20E package and tiny externals ensures a very compact footprint while reducing solution cost. The LT8495’s internal, high efficiency 2A switch delivers efficiencies of up to 83% while operating in a SEPIC configuration. A unique design using dual supply pins (VIN and BIAS) enables the device to operate from the most efficient supply, optimizing efficiency over a wide range of conditions. The LT8495 can operate with input supply voltages up to 60V for SEPIC topologies and up to 32V, with ride-through protection in boost and fly-back topologies. The reset and watchdog timeout periods are independently adjustable using external capacitors. Other features include an FMEA tolerant package, programmable soft-start and thermal shutdown protection. The LT8495 is available in a thermally enhanced TSSOP-20 package. Industrial temperature versions operating from -40C to 125C are also available.