AnalogicTech Offers USB On-The-Go Power

Advanced Analogic Technologies, Inc., (AnalogicTech) announced what it calls the first integrated power solution to conform to the emerging USB On-The-Go (OTG) specification. Using a high efficiency charge pump topology, the AAT3125 regulates output voltage to 5V and supplies up to 100 mA output current. Additionally, all voltage monitoring functionality is integrated to ensure OTG-protocol compatibility.

An addendum to the widely implemented USB 2.0 standard, USB OTG was developed to allow mobile devices and peripherals to communicate with each other without the aid of a PC. Portable devices and peripherals conforming to the spec circumvent the need for PC control by dynamically negotiating a master/slave or “host/peripheral” relationship. By simplifying the device-to-device interface, USB OTG is expected to open up a wide range of new applications for mobile devices.

"While the new standard will allow digital camera users to link directly to a printer or PDA users to link directly to other PDAs or cell phones, power regulation is crucial to ensuring battery life," says Kevin D’Angelo, vice president of engineering from AnalogicTech. "The AAT3125 is the industry’s first complete solution to provide power and port protection for USB OTG dual-role devices."

To meet the requirements of USB OTG, dual role devices must supply a minimum of 8 mA on the 5-V bus to maintain compatibility with the existing USB standard. In addition, the system must be able to step up battery voltage to 5V with maximum efficiency to preserve battery run time. The high efficiency AAT3125, running at 1 MHz, regulates output voltage to 5V and ensures power supply between 8 mA and 100 mA. Moreover, the device’s high switching frequency allows the use of smaller capacitors, which contribute to a smaller footprint, a key consideration in mobile device design.

"While a traditional wired USB port requires 500 mA, that kind of power requirement would kill the battery in a cellular phone or digital still camera," explains Erik Ogren, Product Marketing Manager from AnalogicTech. "We designed the AAT3125 to supply the minimum 8 mA at 5V and negotiate up to 100 mA for ports in mobile devices."

The AAT 3125 is priced at $2.42 in 1,000/unit quantities. Samples and a demo board for the AAT3125 are available immediately. The device comes in a 16-pin 4x4 mm QFN package.