MIC28304

70V 3A Power Module

Hyper Speed Control™ Family

General Description

Micrel’s MIC28304 is synchronous step-down regulator

module, featuring a unique adaptive ON-time control

architecture.

The

module

incorporates

a

DC-to-DC

controller, power MOSFETs, bootstrap diode, bootstrap

capacitor and an inductor in a single package. The

MIC28304 operates over an input supply range from 4.5V

to 70V and can be used to supply up to 3A of output

current. The output voltage is adjustable down to 0.8V with

a guaranteed accuracy of ±1%. The device operates with

programmable

switching

frequency

from

200kHz

to

600kHz.

Micrel’s HyperLight Load™ architecture provides the same

high-efficiency and ultra-fast transient response as the

Hyper Speed Control™ architecture under the medium to

heavy loads, but also maintains high efficiency under light

load conditions by transitioning to variable frequency,

discontinuous-mode operation.

The MIC28304 offers a full suite of protection features.

These include undervoltage lockout, internal soft-start,

foldback

current

limit,

“hiccup”

mode

short-circuit

protection, and thermal shutdown.

Datasheets and support documentation are available on

Micrel’s web site at: www.micrel.com.

Features

• Easy to use

− Stable with low-ESR ceramic output capacitor

− No compensation and no inductor to choose

• 4.5V to 70V input voltage

• Single-supply operation

• Power Good (PG) output

• Low radiated emission (EMI) per EN55022, Class B

• Adjustable current limit

• Adjustable output voltage from 0.9V to 24V

(also limited by duty cycle)

• 200kHz to 600kHz, programmable switching frequency

• Supports safe start-up into a pre-biased output

• –40°C to +125°C junction temperature range

• Available in 64-pin, 12mm × 12mm × 3mm QFN

package

Applications

• Distributed power systems

• Industrial, medical, telecom, and automotive

Typical Application

Hyper Speed Control, HyperLight Load, and Any Capacitor are trademarks of Micrel, Inc.

Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com

March 25, 2014

Revision 1.1