MIC2208 3mm x 3mm 1MHz 3A PWM Buck Regulator General Description Features The Micrel MIC2208 is a high efficiency PWM buck (step- 2.7 to 5.5V supply voltage down) regulator that provides up to 3A of output current. 1MHz PWM mode The MIC2208 operates at 1MHz and has external Output current to 3A compensation that allows a closed loop bandwidth of over >90% efficiency 100kHz. Adjustable output voltage option down to 1V The low on-resistance internal p-channel MOSFET of the MIC2208 allows efficiencies over 94% reduces external Ultra-fast transient response component count and eliminates the need for an External Compensation expensive current sense resistor. Stable with a wide range of output capacitance The MIC2208 operates from 2.7V to 5.5V input and the Fully integrated 5A MOSFET switch output can be adjusted down to 1V. The devices can Micropower shutdown operate with a maximum duty cycle of 100% for use in low- Thermal shutdown and current limit protection dropout conditions. Pb-free 12-pin 3mm x 3mm MLF package The MIC2208 is available in the exposed pad 12-pin 3mm x 3mm MLF package with a junction operating 40C to +125C junction temperature range range from 40C to +125C. Datasheets and support documentation can be found on Applications Micrels web site at: www.micrel.com. 5V or 3.3V Point of Load Conversion Telecom/Networking Equipment Set Top Boxes Storage Equipment Video Cards Typical Application 3A 1MHz Buck Regulator MLF and MicroLeadFrame 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. MIC2208 Ordering Information Part Number Voltage Temperature Range Package Lead Finish MIC2208YML Adj. 40 to +125C 12-Pin 3x3 MLF Pb-Free Note: MLF is GREEN RoHS compliant package. Lead finish is NiPdAu. Mold compound is Halogen Free. Pin Configuration SW 1 12 SW VIN 2 11 VIN PGND 3 10 PGND SGND 4 9 PGOOD BIAS 5 8 EN FB67EP COMP 12-Pin 3mm x 3mm MLF (ML) Pin Description Pin Number Pin Name Pin Function 1, 12 SW Switch (Output): Internal power P-Channel MOSFET output switch. 2, 11 VIN Supply Voltage (Input): Supply voltage for the source of the internal P-channel MOSFET and driver. Requires bypass capacitor to GND 3, 10 PGND Power Ground. Provides the ground return path for the high-side drive current. 4 SGND Signal Ground. Provides return path for control circuitry and internal reference. 5 BIAS Internal circuit bias supply. Must be bypassed with a 0.1F ceramic capacitor to SGND. Feedback. Input to the error amplifier, connect to the external resistor divider 6 FB network to set the output voltage. 7 COMP Compensation. This is the internal error amplifier output. Connect external compensation components for type II or type III compensation. 8 EN Enable (Input). Logic level low will shutdown the device, reducing the current draw to less than 5A. 9 PGOOD Power Good. Open drain output that is pulled to ground when the output voltage is within 7.5% of the set regulation voltage EP GND Connect to ground. M9999-051410-D May 2010 2