DocID025003 Rev 1

9/29

A6727

Device description

4

Device description

The A6727 is a single-phase PWM controller with embedded high-current drivers that

provides complete control logic and protection to realize 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 8-pin device allows a reduction of cost and size of the power

supply solution.

The A6727 is designed to operate from a 5 V to 12 V supply bus. Thanks to the high

precision 0.8 V internal reference, the output voltage can be precisely regulated as low as

0.8 V with ±1% accuracy over line and temperature variations (between 0 °C and +70

°C).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 8 V/µs slew rate, allowing high

regulator bandwidth for fast transient response.

To avoid load damages, the A6727 provides overcurrent protection as well as overvoltage,

undervoltage and feedback disconnection protection. When the device is supplied from 5 V,

overcurrent trip threshold is programmable by a simple resistor. Output current is monitored

sense resistor. Output voltage and feedback disconnection are monitored through FB pin.

The A6727 implements soft-start by increasing the internal reference from 0 V to 0.8 V in 5.1

ms (typ.) in closed loop regulation. Low-side-less feature allows the device to perform the

soft-start over pre-biased output avoiding high-current return through the output inductor

and dangerous negative spikes at the load side.