Bright answer for dimming backlights
Linear Technology
LT3517 and LT3518
DC/DC convertor ICs are ideal for applications such as automotive display backlighting.
New from Linear Technology, the LT3517 and LT3518 are 45V high-side current-sense DC/DC convertors designed to drive high-current LEDs.
Their 3 to 30V input voltage range (with transient protection to 40V) makes them ideal for a wide variety of applications including automotive, industrial and architectural lighting.
The LT3517 and LT3518 are identical except for switch current limits.
The LT3517 has an internal 1.3A switch, whereas the LT3518 has an internal 2.3A switch.
The LT3518 can drive up to ten 350mA white LEDs from a 12V input, whereas the LT3517 can drive five, making them ideal for a variety of applications such as automotive display backlighting.
Both parts can deliver efficiencies up to 90% in boost mode from a compact 4 x 4mm QFN package.
They use true colour PWM dimming to deliver constant LED colour with dimming ranges of more than 3000:1.
For less demanding dimming requirements, the CTRL pin can be used to offer 10:1 analogue dimming.
Their fixed frequency, current mode architecture offers stable operation over a wide range of supply and output voltages.
A frequency adjust pin enables the user to program the frequency between 250kHz and 2.5MHz to optimise efficiency while minimising external component size.
The LT3517 and LT3518 sense output current at the high side of the LED, enabling buck, buck-boost or boost configurations.
Other features include open LED protection, a gate driver for PMOS LED disconnect, and soft-start.
The LT3517EUF and LT3518EUF are both available from stock in 16-pin QFN package, priced starting at US $2.70 and $2.95 each, respectively in 1000-piece quantities.
Extended temperature versions, or "I" Grades, LT3517IUF and LT3518IUF, are also available from stock.
Pricing starts at US $3.24 and $3.54 each respectively in 1000-piece quantities.
Request more information
More stories
Data sheet: LTC3617 monolithic synchronous buck regulator from Linear Technologydownload
The LTC3617 from Linear Technology is a high-efficiency monolithic synchronous buck regulator that utilises a current-mode, constant-frequency architecture.
Linear Technology offers DC/DC controller suitable for sectors such as automotiveweblink
The LT3759 DC/DC controller from Linear Technology — which can generate negative or positive output voltages — is suitable for boost, SEPIC and inverting supply applications within sectors such as industrial, automotive, medical and telecom.
Data sheet: LT3759 current-mode DC/DC controller from Linear Technologydownload
The LT3759 from Linear Technology is a current-mode DC/DC controller that is capable of regulating either positive or negative output voltages from a single feedback pin. It can be configured as a boost, SEPIC or inverting converter.
Linear Technology offers frequency synthesiser for applications such as avionicsweblink
The LTC6946 frequency synthesiser from Linear Technology is suitable for improving the performance of multiband basestations that support LTE, W-CDMA, UMTS, CDMA, GSM and WiMAX standards — as well as point-to-point broadband wireless access, military, avionics, and high-performance test and measurement applications.
Data sheet: LTC6946 integer-N synthesiser with integrated VCO from Linear Technologydownload
The LTC6946 from Linear Technology is a low-noise 5.7GHz phase-locked loop (PLL) with a fully integrated VCO, including a reference divider, a phase-frequency detector with phase-lock indicator, an ultra-low-noise charge pump, an integer feedback divider and a VCO output divider. The charge pump contains selectable high- and low-voltage clamps that are useful for VCO monitoring.
