Linear Technology offers LT3741 DC/DC converter
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LT3741 DC/DC converter
The LT3741 from Linear Technology is a synchronous step-down DC/DC converter that is ideal for applications ranging from battery and supercap chargers and laser drivers to high-current LED lighting.
The LT3741 has been designed to accurately (+/-6 per cent) regulate output currents up to 20A.
It features a 6V to 36V input range, constant current and constant voltage operation.
The LT3741 uses two external switching Mosfets and delivers up to 20A of continuous output current over a wide voltage range of 0V to 34V.
Efficiencies as high as 95 per cent eliminate the need for external heat sinking.
The LT3741's frequency can be programmed and synchronised between 200kHz and 1MHz, allowing designers to optimise efficiency while minimising external component size.
Combined with a 4 x 4mm QFN-20 or thermally enhanced TSSOP-20 package, the LT3741 provides a highly compact constant voltage and current solution.
The LT3741 uses an average current mode control scheme to maintain inductor current regulation over a wide output voltage range of 0V to VIN-2V.
The regulated current is set by an analogue voltage on the CTRL pins and an external sense resistor.
The LT3741's topology enables it to both source and sink current.
Its regulated output voltage and overvoltage protection are set with an external voltage divider.
Additional features include an accurate external voltage reference, a programmable under-voltage lockout (ULVO) pin and thermal shutdown.
The LT3741EUF is available in a 20-pin 4 x 4mm QFN package and the LT3741EFE is available in a thermally enhanced TSSOP-20.
Extended temperature versions - 'I' Grades - the LT3741IUF and LT3741IFE, are also available.
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