July 16, 2015 – Linear Technology Corporation introduced a current mode, fixed frequency SEPIC / boost DC / DC converter lt8494 with an internal 2a, 70V switch. The ultra-low quiescent current of only 7 µ a makes the device very suitable for automotive or other industrial battery power supply systems that remain on all the time. The lt8494 starts in the input voltage range of 2.5V to 32V. Once it starts operation, it works in the input voltage range of 1V to 60V, which is very suitable for applications from a single lithium-ion battery to automotive input power supply. The lt8494 can be configured as a boost, SEPIC or flyback converter. The switching frequency can be set in the range of 250kHz to 1.5MHz through a single resistor, so that the designer can minimize the size of external components. The combination of heat-resistant enhanced tssop-20e or 4mm x 4mm QFN package and slim external components ensures that the solution occupies a very compact board area while minimizing the cost of the solution.
The lt8494’s internal, high efficiency 2A / 70V switch provides up to 83% efficiency while operating in a SEPIC configuration. The unique design of dual power pins (VIN and bias) enables the device to work with the most efficient power supply, thus optimizing efficiency under a variety of conditions. For SEPIC topology, the lt8494 can work with an input power supply of up to 60V, while in boost and flyback topology with ride through protection, the input power supply can be up to 32V. Other features include FMEA fault tolerant package (tssop-20e), power good indicator, programmable soft start and overheat shutdown protection.
Lt8494 is packaged in tssop-20 with enhanced heat resistance.
Performance summary: lt8494
·Wide input voltage range of about 1V to 60V (2.5V to 32V at startup)
·Low ripple burst mode ®） work
。 IQ is 7 µ a at 12vin to 5vout
。 Output ripple (typ.)
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