MIC23050 Datasheet, PDF (1/13 Pages) Micrel Semiconductor – 4MHz PWM Buck Regulator with HYPER LIGHT LOAD™

MIC23050
4MHz PWM Buck Regulator
with HYPER LIGHT LOAD™
General Description
Features
The Micrel MIC23050 is a high efficiency 500mA PWM
synchronous buck (step-down) regulator featuring Hyper
Light Load™, a patented switching scheme that offers
best-in-class light load efficiency and transient
performance while providing very small external
components and low output ripple at all loads.
The MIC23050 also has a very low typical quiescent
current draw of 20µA and can achieve over 85% efficiency
even at 1mA. The device allows operation with a tiny
inductor ranging from 0.47µH to 2.2µH and uses a small
output capacitor that enables a sub-1mm height.
In contrast to traditional light load schemes Hyper Light
Load™ architecture does not need to trade off control
speed to obtain low standby currents and in doing so the
device only needs a small output capacitor to absorb the
load transient as the powered device goes from light load
to full load.
At higher loads the MIC23050 provides a constant
switching frequency of greater than 4MHz while providing
peak efficiencies greater than 93%.
• Input voltage range: 2.7V to 5.5V
• Fixed output voltage options from 0.72V to 2.5V
• Output current guaranteed up to 500mA
• Ultra fast transient response
• 20µA typical quiescent current
• 4MHz in PWM in constant current mode
• Hyper light load mode
• 0.47µH to 2.2µH inductor
• Low voltage output ripple
– 25mVpp in hyper light load mode
– 3mV output voltage ripple in full PWM mode
• >93% efficiency
• ~85% at 1mA
• Fully integrated MOSFET switches
• Micropower shutdown
• Thermal shutdown and current limit protection
• 8-pin 2mm x 2mm MLF^®
• –40°C to +125°C junction temperature range
The MIC23050 comes in fixed output voltage options from
0.72V to 2.5V eliminating external feedback components.
The MIC23050 is available in an 8-pin 2mm x 2mm MLF^®
with a junction operating range from –40°C to +125°C.
Data sheets and support documentation can be found on
Micrel’s web site at: www.micrel.com.
Applications
• Cellular phones
• Digital cameras
• Portable media players
• Wireless LAN cards
• WiFi/WiMax/WiBro modules
• USB Powered Devices
___________________________________________________________________________________________________________
Typical Application
Efficiency V_OUT = 1.8V
100
V_IN = 2.7V
80
V_IN = 3.3V
60
VIN = 3.6V
40
20
V_OUT = 1.8V
L = 1µH
01
10
100
1000
LOAD (mA)
Hyper Light Load is a trademark of Micrel, Inc.
MLF and MicroLeadFrame are registered trademarks of Amkor Technology, Inc.
Protected by US Patent No. 7064531
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel [phone] • fax + 1 [phone] • http://www.micrel.com
July 2007
1
M9999-072007-B