Freescale Semiconductor
Advance Information
Document Number: 34727
Rev. 1.0, 5/2008
600mA High Efficiency Low
Quiescent Current Synchronous
Buck Regulator With Z-mode
The 34727 is a high efficiency, low quiescent current (I
Q
),
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 65µA, 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
• 65µA quiescent current during sleepy Z-mode
• 600mA maximum continuous output current
• Internal 2.0ms soft start
• Thermal and over-current protection
• 0.1µA quiescent current in shutdown (disabled)
• Ultra thin 2x2 UDFN package
• Pb-free packaging designated by suffix code FC
34727
2.7V ~ 5.5V
C
IN
VIN
SW
34727
POWER MANAGEMENT IC
Bottom View
FC SUFFIX (PB-FREE)
98ASA10787D
8-PIN UDFN
2X2
ORDERING INFORMATION
Device
MC34727AFC/R2
MC34727BFC/R2
MC34727CFC/R2
-25°C to 85°C
8-UDFN
Temperature
Range (T
A
)
Package
L1
0.8 - 3.3V *
600mA
FB
ON
OFF
EN
GND
C
OUT
*Programmable
See table 1
Figure 1. 34727 Typical Operating Circuit
* 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.
FREESCALE [ FREESCALE SEMICONDUCTOR, INC ]
