August 23, 2012 - Linear Technology Korea (Representative Hong Sa-gwak, www.linear.com) announced the launch of the H-grade version of LT3518. The LT3518 is a high-side current sense DC/DC converter designed to drive high-current LEDs with constant current. The device operates in an input voltage range of 3V to 30V and provides overvoltage protection up to 40V, making it ideal for various applications such as automotive, industrial, and architectural lighting.
The H-grade version operates at a maximum junction temperature of 150˚C, compared to the E-grade and I-grade versions which have a maximum junction temperature of 125˚C. All electrical specifications for E, I, and H-grade versions are identical. H-grade components are tested and guaranteed at a maximum junction temperature of 150˚C. These products are ideal for automotive and industrial applications where ambient temperatures can be high.
The LT3518 can drive up to eight 300mA white LEDs at 12V input, making it highly suitable for applications such as automotive display backlighting. The LT3518 senses output current on the high-side of the LED, enabling buck, buck-boost, or boost configurations. The device is available in a 4mm x 4mm QFN package form and offers up to 90% efficiency in boost mode. The LT3518 employs True Color PWM™ dimming and provides uniform LED color over a dimming range of 3,000:1 or greater. For lower dimming requirements, the CTRL pin provides 10:1 analog dimming. The device utilizes a fixed frequency and current mode architecture to ensure stable operation over a wide supply and output voltage range. Additionally, through a frequency adjustment pin, users can program the frequency in the range of 250kHz to 2.5MHz to maximize efficiency while minimizing external component size.
The LT3518HUF is supplied in a 16-pin QFN package and starts at $3.79 per unit based on a quantity of 1,000 units. For detailed information, refer to www.linear.com/product/LT3518.

Photo caption: 45V, 2.3A LED Driver, providing 150°C maximum junction temperature

Product Features: LT3518H

• 150°C maximum junction temperature
• 3,000:1 True Color PWM™ dimming ratio
• 2.3A, 45V internal switch
• 100mV high-side current sense
• Open LED protection function
• Adjustable frequency: 250kHz to 2.5MHz
• Wide input voltage range:
o Operating at 3V to 30V
o Overvoltage protection provided up to 40V
• Operation in boost, buck, and buck-boost modes
• PMOS gate driver for LED disconnect
• Constant current and constant voltage regulation
• CTRL pin providing 10:1 analog dimming
• Low shutdown current: <1μA
• Compact (4mm × 4mm) 16-pin QFN package