MILPITAS, CA - April 8, 2010 - Linear Technology announces the H-grade version of the LT3517. The LT3517 is a high side current sense DC/DC converter designed to drive high current LEDs at constant current. Its 3V to 30V input voltage range with transient protection to 40V makes it ideal for a range of applications, including automotive, industrial and architectural lighting. The H-grade version operates with a junction temperature up to 150˚C, compared to the E- and I-grade versions' 125˚C maximum junction temperature. All electrical specifications are identical for the E-, I- and H-grade versions. The H-grade parts are tested and guaranteed to the maximum junction temperature of 150˚C, making them ideal for automotive and industrial applications which are subjected to high ambient temperatures.
The LT3517 can drive up to four 300mA white LEDs from a nominal 12V input, making it ideal for applications such as automotive display backlighting. The LT3517 senses output current at the high side of the LED, enabling buck, buck-boost or boost configurations. The device delivers efficiencies up to 90% in boost mode from a 4mm x 4mm QFN package. The LT3517 offers True Color PWMTM dimming which ensures constant LED color with dimming ranges of up to 5,000:1. For less demanding dimming requirements, the CTRL pin can be used to provide 10:1 analog dimming. Its 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 optimize efficiency while minimizing external component size.
