Micrel Rolls Out New High Performance Power Management IC
Micrel Inc. has launched the MIC2800, a power management IC that provides three output voltages and a power on reset in a 3mm x 3mm MLF®-16 package. The solution is designed for use in cell phones, Smart phones, PDAs, cameras, portable media players, wireless LAN cards and Bluetooth applications. The MIC2800 is currently available in volume and pricing starts at $2.25 each in lots of 1,000.
The MIC2800 features a input range of 2.7V to 5.5V, three voltage outputs and a power-on reset (POR). Output 1 is a high frequency, high efficiency dc-dc switching regulator for up to 600mA while output 2 and 3 are low dropout linear regulators. One of the linear regulators works from a low input voltage, allowing it to post-regulate the switching regulator for best efficiency. For example, the high speed dc-dc converter can step down the Li-ion battery input to 1.8V and the LDO can provide 1.6V by post-regulating the 1.8V rail with greater than 80 percent efficiency. One additional low noise linear output can provide a third voltage such as 2.8V for an analog rail. The IC also offers a LOWQ™ mode that reduces the total current drawn to less than 50µA.
"As cell phone manufacturers add more features such as video streaming and higher resolution cameras to cell phones, several new chipsets have to be powered to enable these applications," noted Ralf Muenster, Micrel's director of marketing for power products. "The MIC2800 is a no compromise design, meeting the requirements of camera accelerator DSPs or digital multimedia broadcast (DMB) chips used in today's portable applications with the smallest footprints. In addition to these and other auxiliary functions, the part is also suitable to powering a baseband processor core and I/O rails as well as providing a higher low noise analog voltage using the third output."
The dc-dc converter provides virtually no noise in light load mode and just 75µVRMS output noise in LOWQ™ mode. This allows designers to avoid higher noisy light-load modes that have traditionally interfered with sensitive RF circuitry. The solution operates at 2MHz pulse width modulation in normal mode, more than 93 percent efficiency and requires a 2.2µF output capacitor and a 2.2µH inductor for stability. The part also integrates a POR circuit that monitors all three outputs. Independent enables for the switching and two linear regulators allow for design flexibility.
