High-current synchronous buck regulator offers high efficiency with integrated high- and low-side switches

Worcester, MA The new A8672 from Allegro MicroSystems Europe is a synchronous buck regulator IC capable of delivering high currents (up to 8 A) through the use of low “on” resistance internal switches. It uses valley current mode control, which allows very short “on” times to be achieved and inherently provides improved transient response over traditional switching schemes through the use of a voltage feed-forward loop and frequency modulation during large signal load changes.
 
The A8672 includes a comprehensive set of diagnostic flags, allowing the host platform to react to a myriad of different fault conditions. A fault output indicates when either the temperature is becoming unusually high, or a single point failure has occurred - such as the switching node shorted to ground or the timing resistor going open-circuit.
 
A “power OK” output is also provided after a fixed delay to indicate when the output voltage is within regulation. The selectable pulse-by-pulse current limit avoids the need to oversize the inductor to cope with large fault currents.
 
This device is targeted at the industrial, consumer and computer markets. Typical applications include servers and networking systems that require 5 V or 12 V input stepdown conversions at high output current.
 
The A8672 is available in a 4 mm x 5 mm, 28-contact QFN package (suffix EG) with exposed pad for enhanced thermal performance.
 
About Allegro
Allegro MicroSystems, LLC is a leader in developing, manufacturing and marketing high-performance semiconductors. Allegro's innovative solutions serve high-growth applications within the automotive market, with additional focus on office automation, industrial, and consumer/communications solutions. Allegro is headquartered in Worcester, Massachusetts (USA) with design, applications, and sales support centers located worldwide. Further information about Allegro can be found at www.allegromicro.com
 
Allegro MicroSystems Europe, headquartered in Chertsey, United Kingdom, is the European sales and marketing operation, and operates a network of representatives and distributors throughout Europe.  Allegro also has an engineering design centre in Edinburgh in Scotland and an application and marketing centre in Annecy in France.