L6728AH

Device description

Doc ID 15726 Rev 1

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Device description

L6728AH 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 VFQFPN10 3x3 mm.

L6728AH 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 ±1% accuracy over line and temperature

variations. The switching frequency is internally set to 600 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 8 V/µs slew rate, allowing high

regulator bandwidth for fast transient response.

To avoid load damages, L6728AH provides over-current protection as well as overvoltage,

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.

L6728AH 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.

L6728AH is available in a compact VFDFN10 3 x 3 mm package with exposed pad.