New Industry Products

Linear Tech Releases 60V Input, Low Quiescent Current Step-Down Controller

April 22, 2009 by Jeff Shepard

Linear Technology Corp. announced the H-grade version of the LTC3824, a 4V to 60V input range, low quiescent current step-down dc-dc controller in a small thermally enhanced MSOP-10 package.

This H-grade device is guaranteed up to a 150°C operating junction temperature range and is ideal for automotive and industrial applications subjected to high ambient temperatures, demanding a small solution size for output voltages ranging from 0.8V to VIN at up to 5A. The device’s 4V minimum input voltage supports automotive cold crank and the 60V maximum input voltage survives inductive load dumps without the need for external clamping circuits.

The LTC3824H can be configured for Burst Mode® operation, which reduces the controller’s no load current draw to only 40µA and safely powers pre-biased loads. The shutdown current is a mere 7µA. With 100% duty cycle capability, the LTC3824H has a very low dropout voltage, allowing VOUT to approach VIN, a feature that extends the run-time in battery-powered applications. In addition, the LTC3824H can be programmed to a fixed frequency from 100kHz to 600kHz.

For noise-sensitive applications, the device can be synchronized to an external clock over the same range. Its strong onboard MOSFET gate driver powers an external P-channel MOSFET to produce greater than 90% conversion efficiency. Furthermore, the LTC3824H’s current mode architecture provides fast line and load transient response as well as cycle-by-cycle overcurrent protection. Additional features include programmable current limit and soft-start, along with overvoltage protection.

The LTC3824H operates and is guaranteed over an operating junction temperature range of -40 to 150°C. 1,000-piece pricing starts at $2.55 each.