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 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