MIC4721YMM

MIC4721 1.5A 2MHz Integrated Switch Buck Regulator General Description Features The Micrel MIC4721 is a high efficiency PWM buck (step- 2.7 to 5.5V supply voltage down) regulators that provides up to 1.5A of output 2MHz PWM mode current. The MIC4721 operates at 2MHz and has Output current to 1.5A proprietary internal compensation that allows a closed loop Up to 94% efficiency bandwidth of over 200KHz. 100% maximum duty cycle The low on-resistance internal p-channel MOSFET of the Adjustable output voltage option down to 1V MIC4721 allows efficiencies up to 94%, 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 capacitor The MIC4721 operates from 2.7V to 5.5V input and the Fully integrated 1.5A 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- Power Good pin dropout conditions. Thermal shutdown and current limit protection The MIC4721 is available in the 10-pin MSOP package Pb-free 10-pin 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 Micrels web site at: www.micrel.com. Applications 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 5V to 3.3V Efficiency IN O 94 92 90 88 86 84 82 80 78 1.5A 2MHz Buck Regulator 76 0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 OUTPUT CURRENT (A) Micrel Inc. 2180 Fortune Drive San Jose, CA 95131 USA tel +1 (408) 944-0800 fax + 1 (408) 474-1000 Micrel, Inc. MIC4721 Ordering Information Part Number Voltage Temperature Range Package Lead Finish MIC4721YMM Adj. 40 to +125C 10-Pin MSOP Pb-Free Pin Configuration SW 1 10 SW VIN 2 9 VIN SGND 3 8 PGND BIAS 4 7 PGOOD FB 5 6 EN 10-Pin MSOP (MM) Pin Description Pin Number Pin Name Pin Function 1, 10 SW Switch (Output): Internal power P-Channel MOSFET output switch. 2, 9 VIN Supply Voltage (Input): Supply voltage for the source of the internal P-channel MOSFET and driver. Requires bypass capacitor to GND. 3 SGND Signal (Analog) Ground. Provides return path for control circuitry and internal reference. 4 BIAS Internal circuit bias supply. Must be bypassed with a 0.1F ceramic capacitor to SGND. 5 FB Feedback. Input to the error amplifier, connect to the external resistor divider network to set the output voltage. 6 EN Enable (Input). Logic level low will shutdown the device, reducing the current draw to less than 5A. Power Good. Open drain output that is pulled to ground when the output voltage 7 PGOOD is within 7.5% of the set regulation voltage. 8 PGND Power Ground. Provides the ground return path for the high-side drive current. M9999-052907-A May 2007 2