L6728

Device description

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Device description

L6728 is a single-phase PWM controller with embedded high-current drivers that provides

complete control logic and protections to realize in an easy and simple way a general DC-

DC step-down converter. Designed to drive N-channel MOSFETs in a synchronous buck

topology, with its high level of integration this 10-pin device allows reducing cost and size of

the power supply solution also providing real-time PGOOD in a compact DFN10 3x3 mm.

L6728 is designed to operate from a 5 V or 12 V supply. The output voltage can be precisely

regulated to as low as 0.8 V with ±0.8 % accuracy over line and temperature variations. The

switching frequency is internally set to 300 kHz.

This device provides a simple control loop with a voltage-mode error-amplifier. The error-

amplifier features a 15 MHz gain-bandwidth product and 8V/µs slew rate, allowing high

regulator bandwidth for fast transient response.

To avoid load damages, L6728 provides over current protection as well as over voltage,

under voltage and feedback disconnection protection. The over current trip threshold is

programmable by a simple resistor connected from Lgate to GND. Output current is

consuming sense resistor. Output voltage is monitored through dedicated VSEN pin.

L6728 implements soft-start increasing the internal reference in closed loop regulation.

Low-side-less feature allows the device to perform soft-start over pre-biased output avoiding

high current return through the output inductor and dangerous negative spike at the load

side.

L6728 is available in a compact DFN10 3x3 mm package with exposed pad.