MIC2238
2.5MHz Dual Phase
PWM Buck Regulator
General Description Features
The Micrel MIC2238 is dual output 2-phase synchronous
Input voltage range: 2.5V to 5.5V
buck (step down) PWM DC/DC switching regulator. Power
Dual output voltages running out of phase
conversion efficiencies of above 95% are easily obtainable
28A quiescent current
for a wide range of applications and loads. An ultra-low
Fixed output voltage versions
quiescent current of 28A at light loads assures minimum
current draw in battery powered applications that require Adjustable version down to 0.8V
standby modes. The 2.5MHz PWM operation of MIC2238
Low noise 2.5MHz PWM operation
allows the use of miniature 1H, 2.2H or 4.7H inductor
800mA output current capability for each channel
with the use of 2.2F ceramic output capacitor.
Stable with 2.2H inductor, 2.2F ceramic cap
The MIC2238 operates from 2.5V to 5.5V input and is
Automatic switching into light load mode of operation
available in fixed output voltage versions to save space
/FPWM pin allows low noise all-PWM mode operation
and reduce external component count. The MIC2238-AAs
(adjustable version) output voltage versions can be
Power good output with internal 5A current source
programmed as low as 0.8V
allows sequencing with programmable delay time
For applications that require the lowest noise performance,
Internal soft-start
the /FPWM pin allows the automatic Trickle mode to be
1A shutdown current
disabled, remaining in full PWM mode. To maximize
Built-in soft-start circuitry
battery life in low-dropout conditions, MIC2238 can
Current limit protection
operate with a maximum duty cycle of 100%.
Pb-Free 3mm x 3mm MLF -12L package
The MIC2238 is available in a space-saving 3mm x 3mm
MLF -12L package with a junction temperature range from
Applications
-40C to +125C.
Cellular phones
Data sheets and support documentation can be found on
PDAs
Micrels web site at www.micrel.com.
Digital Cameras
MP3 Players
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Typical Application
MLF and MicroLead Frame are registered trademarks of Amkor Technology, Inc.
Micrel Inc. 2180 Fortune Drive San Jose, CA 95131 USA tel +1 (408) 944-0800 fax + 1 (408) 474-1000 Micrel, Inc. MIC2238
Ordering Information
Part Number V V Junction Package Lead Finish
OUT1 OUT2
Temperature Range
MIC2238-AAYML Adj. Adj. 12-Pin 3mm x 3mm MLF Pb-Free
40C to +125C
MIC2238-521YML 1.28V 1.65V 12-Pin 3mm x 3mm MLF Pb-Free
40C to +125C
MIC2238-G4YML 1.8V 1.2V 40C to +125C 12-Pin 3mm x 3mm MLF Pb-Free
MIC2238-GF9YML 1.8V 1.545V 12-Pin 3mm x 3mm MLF Pb-Free
40C to +125C
MIC2238-GFHYML 1.8V 1.575V 40C to +125C 12-Pin 3mm x 3mm MLF Pb-Free
MIC2238-GSYML 1.8V 3.3V 40C to +125C 12-Pin 3mm x 3mm MLF Pb-Free
MIC2238-GWYML 1.8V 1.6V 40C to +125C 12-Pin 3mm x 3mm MLF Pb-Free
MIC2238-J4YML 2.5V 1.2V 40C to +125C 12-Pin 3mm x 3mm MLF Pb-Free
MIC2238-S4YML 3.3V 1.2V 40C to +125C 12-Pin 3mm x 3mm MLF Pb-Free
MIC2238-SSYML 3.3V 3.3V 40C to +125C 12-Pin 3mm x 3mm MLF Pb-Free
Note:
Other voltages available. Contact Micrel Marketing for details.
MLF is a GREEN RoHS compliant package. Lead finish is NiPdAu. Mold compound is Halogen Free.
Pin Configuration
Adjustable Fixed
MIC2238-AAYML MIC2238-xxYML
12-Pin MLF (ML) 12-Pin MLF (ML)
(Top View) (Top View)
M9999-040810-A
April 2010 2