MIC33153

4MHz PWM 1.2A Internal Inductor

Buck Regulator with HyperLight Load™

and Power Good

HyperLight Load is a trademark of Micrel, Inc.

MLF and MicroLeadFrame are registered trademark Amkor Technology Inc.

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

General Description

The

MIC33153

is

a

high-efficiency

4MHz

1.2A

synchronous buck regulator with an internal inductor,

HyperLight Load™ mode, Power Good (PG) output

indicator, and programmable soft start. HyperLight Load™

provides very high efficiency at light loads and ultra-fast

transient response which makes the MIC33153 perfectly

suited for supplying processor core voltages. An additional

benefit of this proprietary architecture is very low output

ripple voltage throughout the entire load range with the use

of small output capacitors.

The MIC33153 is designed so that only two external

capacitors as small as 2.2µF are needed for stability. This

gives the MIC33153 the ease of use of an LDO with the

efficiency of a HyperLight Load™ DC converter. The

MIC33153 achieves efficiency in HyperLight Load

as high as 85% at 1mA, with a very low quiescent current

of 22µA. At higher loads, the MIC33153 provides a

constant switching frequency up to 4MHz.

The MIC33153 is available in 14-pin 3.0mm x 3.5mm

MLF

range from –40

°C to +125°C.

Datasheets and support documentation can be found on

Micrel’s web site at: www.micrel.com.

Features

• Internal inductor

− Simplifies design to two external capacitors

• Input voltage: 2.7V to 5.5V

• Output voltage: fixed or adjustable (0.62V to 3.6V)

• Up to 1.2 A output current

• Up to 93% peak efficiency

• 85% typical efficiency at 1mA

• Power Good (PG) output

• Programmable soft start

• 22µA typical quiescent current

• 4MHz PWM operation in continuous mode

• Ultra-fast transient response

• Low ripple output voltage

− 35mVpp ripple in HyperLight Load

− 7mV output voltage ripple in full PWM mode

• 0.01µA shutdown current

• Thermal shutdown and current limit protection

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

Applications

• Solid State Drives (SSD)

• Mobile handsets

• Portable media/MP3 players

• Portable navigation devices (GPS)

• WiFi/WiMax/WiBro modules

• Wireless LAN cards

• Portable applications

____________________________________________________________________________________________________________

Typical Application

Fixed Output Voltage

Adjustable Output Voltage

September 2010

M9999-092910-A