“Today’s portable applications continue to demand increasingly smaller solution sizes. Cell phone manufacturers in particular, are competing with each other to provide the consumer with the sleekest phones while increasing functionality at the same time,” noted Ralf Muenster, Micrel’s director of marketing for power products. “By using a 470 nH chip inductor, Micrel offers designers the only step-down regulator that enables a sub-1mm height solution. This will enable cell phone manufacturers to design more appealing slimmer phones.”

Besides its small size, the MIC2285 high efficiency solution also features ultra-low noise and fast transient response. By incorporating a LOWQTM LDO mode, the MIC2285 offers the best of both worlds. Under light load conditions, it can be switched into the LDO mode using a LOWQ pin, offering low noise operation with fast transient response, while at full loads it offers the efficiency of a PWM buck regulator.

In portable applications, the processor consumes a minimal current during sleep mode. In the LDO mode, the MIC2285 offers good efficiency since it consumes a mere 20uA quiescent current. When the processor wakes up from sleep mode to full power mode, the LDO in the MIC2285 is able to provide the current step required with minimal output capacitance while the switching regulator takes over to power the processor. Other regulators commonly used in the industry today employ a PFM scheme at light loads. While this achieves good light-load efficiency, transient response suffers, resulting in the need for approximately five times the output capacitance in order to achieve a tightly regulated output voltage. This not only increases the cost of the design, but also results in a much larger solution.

The IC operates from 2.7V to 5.5V input and features internal power MOSFETs that can supply up to 500mA output current in PWM mode. It can also operate with a maximum duty cycle of 100 percent for use in low dropout conditions. The MIC2285 is available in the 10-pin 3mm x 3mm MLF™ package with a junction operating range from –40°C to +125°C.

About Micrel, Inc.
Micrel Inc., is a leading global manufacturer of IC solutions for the worldwide analog, Ethernet and high bandwidth markets. The Company’s products include advanced mixed-signal, analog and power semiconductors; high performance communication, clock management, Ethernet switch and physical layer transceiver ICs. Company customers include leading manufacturers of enterprise, consumer, industrial, mobile, telecommunications, automotive, and computer products. Corporation headquarters and state-of-the-art wafer fabrication facilities are located in San Jose, CA with regional sales and support offices and advanced technology design centers situated throughout the Americas, Europe and Asia. In addition, the Company maintains an extensive network of distributors and reps worldwide. Web: http://www.micrel.com.

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Note: MLF is a trademark of Amkor Technology. LOWQ is a trademark of Micrel, Inc.

Contact:
Julieanne DiBene, Marketing Communications
1-408-474-1276
Julie.DiBene@Micrel.com