Linear Technology offers LT3741 DC/DC converter
Linear Technologycontact supplier
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.
The LTC3624 is a high-efficiency, 17V-input-capable synchronous buck regulator from Linear Technology that delivers up to 2A of continuous output current to outputs as low as 0.6V. Synchronous rectification delivers efficiencies as high as 95 per cent, while Burst Mode operation requires only 3.5µA of no-load quiescent current.
The LT8471 from Linear Technology is a dual DC/DC converter that utilises two internal 2A, 50V switches and an additional 500mA switch to facilitate step-down, step-up and inverting conversion. Each 2A channel can be independently configured as a buck, boost, SEPIC, flyback, ZETA or inverting DC/DC converter. This range of topologies and output configurations makes the device suitable for industrial and automotive applications.
As Linear Technology’s Jim Williams explains, a large group of fibre-optic lasers are powered by DC current. Laser drive is supplied by a current source with modulation added further along the signal path. The current source, although conceptually simple, constitutes a tricky design problem. There are a number of practical requirements for a fibre-optic current source and failure to consider them can cause laser and/or optical component destruction.
Linear Technology has introduced the LTC6431-20: a 20MHz to 2GHz single-ended input and output fixed-gain amplifier that offers a 46.2dBm OIP3 (output third-order intercept) and a 2.6dB noise figure. Two grades are offered, including the A-grade version that has a minimum of 42.2dBm OIP3 at 240MHz and the B-grade version that has a typical OIP3 of 45.7dBm at the same frequency.
Continued demands for increased bandwidth have resulted in deployment of fibre-optic-based networks. This application note discusses ‘climactic pampering for temperamental lasers’.