MIC23031 Datasheet, PDF (1/17 Pages) Micrel Semiconductor – 4MHz PWM 400mA Buck Regulator with Hyper Light Load™

MIC23031
4MHz PWM 400mA Buck Regulator
with Hyper Light Load™
General Description
The MIC23031 is a high efficiency 4MHz 400mA
synchronous buck regulator with Hyper Light Load™
mode. Hyper Light Load™ provides very high efficiency at
light loads and ultra-fast transient response which is
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 tiny 1.6mm x
1.6mm Thin MLF^® package saves precious board space
and requires only three external components.
The MIC23031 is designed for use with a very small
inductor, down to 0.47µH, and an output capacitor as small
as 2.2 µF that enables a sub-1mm height.
The MIC23031 has a very low quiescent current of 21µA
and achieves as high as 88% efficiency at 1mA. At higher
loads, the MIC23031 provides a constant switching
frequency around 4MHz while achieving peak efficiencies
up to 93%.
The MIC23031 is available in a 6-pin 1.6mm x 1.6mm Thin
MLF^® package with an operating junction temperature
range from –40°C to +125°C.
Data sheets and support documentation can be found on
Micrel’s web site at: www.micrel.com.
Features
• Input voltage range: 2.7V to 5.5V
• 400mA output current
• Up to 93% efficiency and 88% at 1mA
• 21µA typical quiescent current
• 4MHz PWM operation in continuous mode
• Ultra fast transient response
• Low voltage output ripple
o 20mVpp ripple in Hyper Light Load^TM mode
o 3mV output voltage ripple in full PWM mode
• Fully integrated MOSFET switches
• 0.01µA shutdown current
• Thermal shutdown and current limit protection
• Fixed and adjustable output voltage options available
• 6-pin 1.6mm x 1.6mm Thin MLF^®
• –40°C to +125°C junction temperature range
Applications
• Mobile handsets
• Portable media/MP3 players
• Portable navigation devices (GPS)
• WiFi/WiMax/WiBro modules
• Digital Cameras
• Wireless LAN cards
• USB powered devices
• Portable applications
Typical Application
U1 - MIC23031
VIN
VIN
L1
SW
C1
EN
EN
SNS
GND
AGND PGND
VOUT
C2
GND
Efficiency VOUT = 2.5V
100
= 3.0V
90
80
= 4.2V
= 3.6V
70
60
L
501
10
100
1000
OUTPUT CURRENT (mA)
Hyper Light Load is a trademark of Micrel, Inc
MLF and MicroLead Frame are registered trademark Amkor Technology Inc.
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel [phone] • fax + 1 [phone] • http://www.micrel.com
May 2008
M9999-051608-A