Linear Technology Introduces Narrow/Wide Input Voltage Range Synchronous Step-Down DC/DC Controllers

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Linear Technology Corporation (Linear Technology Corporation) Release narrow / wide input voltage range (2.7V to 5.5V or 4V to 38V) synchronous step-down DC / DC controller LTC3852. The device's built-in charge pump provides a 5V bias voltage to drive low RDS (ON) and standard logic level power MOSFETs from a nominal 3.3V supply. Because the LTC3852 's internal charge pump and DC/DC controller are independent of each other, the charge pump can provide a 5V output to power the internal gate driver, while the DC/DC converter can be powered from another source (maximum up to 38V) draw power. The LTC3852 delivers up to 25A of output current over an output voltage range of 0.8V to 99% VIN (2.7V to 5.5V), making the device ideal for 3.3V powered point-of-load applications.

The constant frequency current mode architecture allows for an optional fixed or phase-lockable (PLL) frequency from 250kHz to 750kHz. Optional Burst Mode? Operation, pulse skipping or forced continuous mode is user controlled to optimize efficiency at light loads. OPTI-LOOP® compensation allows for optimized transient response over a wide range of output capacitors and ESR values, including all ceramic input and output capacitors. Output current sensing is accomplished by measuring the voltage drop across the output inductor (DCR) for maximum efficiency, or by using an optional sense resistor in series with the inductor (for maximum accuracy) ). The current foldback feature limits MOSFET heat dissipation during short and overload conditions.

In addition, the LTC3852 features adjustable soft-start or tracking to control the power-on characteristics and an accurate 0.8V reference with an accuracy of ±1.25% over the -40°C to 125°C operating temperature range. With a maximum duty cycle of 99%, the LTC3852 has a very low dropout voltage, which is a very useful feature for extending run time in battery-powered applications.

The LTC3852 is available in a thermally enhanced 3mm x 5mm QFN-24 package. The 1,000-piece purchase price is $1.95 per piece and is available from stock. For more information, please visit

Photo Caption: Low Voltage Synchronous Step-Down DC/DC Controller