MIC2202_07 Datasheet, PDF (1/19 Pages) Micrel Semiconductor – High Efficiency 2MHz Synchronous Buck Converter 1μF Stable PWM Regulator

MIC2202
High Efficiency 2MHz Synchronous Buck
Converter 1µF Stable PWM Regulator
General Description
Features
The Micrel MIC2202 is a high efficiency 2MHz PWM • Input voltage range: 2.3V to 5.5V
synchronous buck regulator. The fast 2MHz operation _{• Output down to 0.5V/600mA}
along with a proprietary compensation scheme allows the
smallest possible external components. The MIC2202 can
operate with a 1µF ceramic output capacitor and a small,
low DC-resistance, 2.2µH inductor, reducing system size
and cost while allowing a high level of efficiency.
The MIC2202 operates from 2.3V to 5.5V input and
features internal power MOSFETs that can supply over
600mA of output current with output voltages down to
0.5V. The MIC2202 implements a constant 2MHz pulse-
width-modu-lation (PWM) control scheme which reduces
noise in sensitive RF, audio, and communications
applications. Additionally, the MIC2202 can be
synchronized to an external clock, or multiple MIC2202s
can easily be daisy-chained with the SYNCLOCK feature.
The MIC2202 has a high bandwidth loop (up to 500kHz)
which allows ultra fast transient response times. This is
very useful when powering applications that require fast
• 2MHz PWM operation
• Stable with 1µF ceramic output capacitor.
• Ultra-fast transient response (up to 500kHz GBW)
• Internal compensation
• All ceramic capacitors
• >95% efficiency
• Fully integrated MOSFET switches
• Easily synchronized to external clock
• SYNCLOCK feature to daisy chain multiple 2202s
• Requires only 4 external components
• 1% line and load regulation
• Logic controlled micropower shutdown
• Thermal shutdown and current limit protection
• 10-pin MSOP and 10-pin 3mm×3mm MLF^® package
options
• –40°C to +125°C junction temperature range
dynamic response such as CPU cores and RF circuitry in
high performance cellular phones and PDAs. The ^Applications
MIC2202 is available in 10-pin MSOP and 10-pin 3mm ×
3mm MLF^® package options 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.
• Cellular phones
• PDAs
• 802.11 WLAN power supplies
• FPGA/ASIC power supplies
• Dynamically adjustable power supply for CDMA/W-
CDMA RF power amps
• DSL modems
• Tape drives
___________________________________________________________________________________________________________
Typical Application
2.2µH
V_IN
1
2.3V to 5.5V
2
SYNC_IN
3
SYNC_OUT
4
EN
5
10
9
10k
8
7
10nF
6
1.78k
V_OUT
3.3V
600mA
1µF
Adjustable Output Synchronous Buck Regulator
100
95
90
85
80
75
70
65
60
0
Efficiency 3.3V_OUT
4.2V_IN
5V_IN
L = 2.2µH
C_OUT = 1µF
0.1 0.2 0.3 0.4 0.5 0.6
OUTPUT CURRENT (A)
MLF and MicroLeadFrame are registered trademarks of Amkor Technology, Inc.
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel [phone] • fax + 1 [phone] • http://www.micrel.com
March 2007
1
M9999-031907