Document Number: 34727

Rev. 1.0, 5/2008

Freescale Semiconductor

Advance Information

* This document contains certain information on a new product.

Specifications and information herein are subject to change without notice.

© Freescale Semiconductor, Inc., 2008. All rights reserved.

600mA High Efficiency Low

Quiescent Current Synchronous

Buck Regulator With Z-mode

synchronous buck regulator, implementing Freescale’s innovative

Z-mode architecture. Freescale’s Z-mode architecture greatly

improves the ripple performance during light load currents, but still

maintains a low quiescent current of 65

µA, at no load in “Sleepy” Z-

mode.

The 34727 accepts an input voltage in the range of 2.7 to 5.5V,

making it ideally suited for single cell Li-Ion based applications. Factory

preset output voltages, ranging from 0.8 to 3.3V, reduce the number of

required auxiliary components. The part is able to provide 600mA of

continuous load current across the input and the output voltage ranges.

The 34727 switches at 2.0MHz to allow the use of small surface

mount inductors and capacitors, to save precious board space.

The 34727 is available in the small, space saving, and low cost, 2x2

UDFN-8 packages. The part is guaranteed for operation over the -25°C

to +85°C temperature range.

Features

• 94% peak efficiency

• 2.0MHz switching frequency

• Automatic transition to energy saving light load Z-mode (low ripple)

• 2.7V to 5.5V input voltage range

• Fixed output voltage options from 0.8V to 3.3V

•65

µA quiescent current during sleepy Z-mode

• 600mA maximum continuous output current

• Internal 2.0ms soft start

• Thermal and over-current protection

•0.1

µA quiescent current in shutdown (disabled)

• Ultra thin 2x2 UDFN package

• Pb-free packaging designated by suffix code FC

Figure 1. 34727 Typical Operating Circuit

POWER MANAGEMENT IC

FC SUFFIX (PB-FREE)

98ASA10787D

8-PIN UDFN

2X2

34727

ORDERING INFORMATION

Device

Temperature

Package

MC34727AFC/R2

-25°C to 85°C

8-UDFN

MC34727BFC/R2

MC34727CFC/R2

Bottom View

VIN

EN

SW

FB

GND

ON

OFF

2.7V ~ 5.5V

0.8 - 3.3V *

600mA

34727

L1

*Programmable

See table 1