MIC4724 3A 2MHz Integrated Switch Buck Regulator with 6Vmax Input General Description Features The Micrel MIC4724 is a high efficiency PWM buck (step- 3.0 to 6.0V supply voltage down) regulator that provides up to 3A of output current. 2.0MHz PWM mode The MIC4724 operates at 2.0MHz and has proprietary Output current to 3A internal compensation that allows a closed loop bandwidth Up to 94% efficiency of over 200KHz. 100% maximum duty cycle The low on-resistance internal p-channel MOSFET of the Adjustable output voltage option down to 1V MIC4724 allows efficiencies over 92%, reduces external Ultra-fast transient response components count and eliminates the need for an Ultra-small external components expensive current sense resistor. Stable with a 1H inductor and a 4.7F output The MIC4724 operates from 3.0V to 6.0V input and the capacitor output can be adjusted down to 1V. The devices can Fully integrated 3A MOSFET switch operate with a maximum duty cycle of 100% for use in low- Micropower shutdown dropout conditions. Thermal shutdown and current limit protection The MIC4724 is available in 10-pin ePAD MSOP package Pb-free 10-pin ePAD MSOP package with a junction operating range from 40C to +125C. 40 C to +125 C junction temperature range Data sheets and support documentation can be found on Applications Micrels web site at: www.micrel.com. FPGA/DSP/ASIC applications General point of load Broadband communications DVD/TV recorders Point of sale Printers/Scanners Set top boxes Computing peripherals Video cards Typical Application 3.3V Efficiency OUT 96 4.5V IN 94 5V IN 92 90 5.5V IN 88 86 84 82 80 78 3A 2MHz Buck Regulator 76 0 0.5 1 1.5 2 2.5 3 OUTPUT CURRENT (A) 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. MIC4724 Ordering Information Part Number Voltage Temperature Range Package Lead Finish MIC4724YMME Adj. 40 to +125C 10-Pin ePAD MSOP Pb-Free Note This is a GREEN RoHS compliant package. Lead finish is NiPdAu. Mold compound is Halogen Free. Pin Configuration SW 1 10 SW VIN 2 9 VIN SGND 3 8 PGND BIAS 4 7 PGOOD EP FB 5 6 EN 10-Pin ePAD MSOP (MME) Pin Description Pin Pin Pin Function Number Name 1, 10 SW Switch (Output): Internal power P-Channel MOSFET output switch. VIN Supply Voltage (Input): Supply voltage for the source of the internal P-channel MOSFET 2, 9 and driver. Requires bypass capacitor to GND. PGND Power Ground. Provides the ground return path for the high-side drive current. 8 SGND Signal (Analog) Ground. Provides return path for control circuitry and internal reference. 3 BIAS Internal circuit bias supply. Must be bypassed with a 0.1F ceramic capacitor to SGND. 4 FB Feedback. Input to the error amplifier, connect to the external resistor divider network to 5 set the output voltage. EN Enable (Input). Logic level low, will shutdown the device, reducing the current draw to 6 less than 5A. PGOOD Power Good. Open drain output that is pulled to ground when the output voltage is 7 within 7.5% of the set regulation voltage. ePAD Connect to ground. EP M9999-062408-A June 2008 2