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Device description

The A6727B 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 A6727B 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 ±1.5 % accuracy over 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 8 V/µs slew rate, allowing high regulator

bandwidth for fast transient response.

To avoid load damages, the A6727B 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 through low-side MOSFET RDS(on), saving the use of expensive and space-

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

The A6727B 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.

A6727B

Device description

DS14159 - Rev 2

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