Linear Technology step-down controller

Linear Technology has announced a high reliability grade version of the LTC3824, a 4-60 V input range, low quiescent current, 100% duty step-down DC/DC controller in a small thermally enhanced MSOP-10 package.

The device is specified over the -55 to +125°C operating junction temperature range and is suitable for space-constrained, industrial, telecom, datacom and battery-powered applications that demand an output voltage ranging from 0.8 to V_IN, at up to 5 A.

The 4 V minimum input supports motor vehicle cold crank conditions and the 60 V maximum input voltage survives inductive load dumps without the need for external clamping.

The controller can be configured for Burst Mode operation, which reduces the device's no load current draw to 40 µA and safely powers pre-biased loads. The shutdown current is 7 µA. With 100% duty cycle capability, the controller has a low dropout voltage, allowing V_OUT to approach V_IN, a feature that extends the run-time in battery-powered applications.

In addition, it can be programmed to a fixed frequency from 100-600 kHz. For noise-sensitive requirements, the device can be synchronised to an external clock over the same range. Its strong onboard MOSFET gate driver powers an external P-channel MOSFET to produce up to 90% conversion efficiency.

The device'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.