MIC27600

36V, 7A Hyper Speed Control

™

Synchronous DC-DC Buck Regulator

SuperSwitcher II

™

Hyper Speed Control, SuperSwitcher II and Any Capacitor are trademarks of Micrel, Inc.

MLF and MicroLeadFrame are registered trademarks of Amkor Technology, Inc.

Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (

General Description

The Micrel MIC27600 is a constant-frequency, synchronous

buck regulator featuring a unique digitally-modified adaptive

on-time control architecture. The MIC27600 operates over an

input supply range of 4.5V to 36V and provides a regulated

output of up to 7A of output current. The output voltage is

adjustable down to 0.8V with a guaranteed accuracy of ±1%,

and the device operates at a switching frequency of 300kHz.

Micrel’s Hyper Speed Control

™ architecture allows for ultra-

fast transient response while reducing the output capacitance

combines the advantages of fixed-frequency operation and

fast transient response in a single device.

The MIC27600 offers a full suite of protection features to

ensure protection of the IC during fault conditions. These

include undervoltage lockout to ensure proper operation

under power-sag conditions, internal soft-start to reduce

inrush current, foldback current limit, “hiccup” mode short-

circuit protection and thermal shutdown.

All support documentation can be found on Micrel’s web

site at: www.micrel.com.

Features

•

Hyper Speed Control

™ architecture enables

-

-

Small output capacitance

•

4.5V to 36V voltage input

•

•

•

±1% FB accuracy

•

Any Capacitor

™ Stable - Zero-ESR to high-ESR

•

7A output current capability, up to 95% efficiency

•

300kHz switching frequency

•

Internal compensation, 6ms Internal soft-start

•

Foldback current-limit and “hiccup” mode short-circuit

protection

•

Thermal shutdown

•

Supports safe startup into a pre-biased load

•

–40

°C to +125°C junction temperature range

•

28-pin 5mm

Applications

•

Distributed power systems

•

Communications/networking infrastructure

•

Set-top box, gateways and routers

•

Printers, scanners, graphic cards and video cards

___________________________________________________________________________________________________________

Typical Application

vs. Output Current

60

65

70

75

80

85

90

95

01

234

567

89

OUTPUT CURRENT (A)

5.0V

3.3V

2.5V

1.8V

1.5V

1.2V

1.0V

0.9V

0.8V

July 2011

M9999-070811