AnalogicTech Introduces New PMICs To Extend Battery Life
Advanced Analogic Technologies Inc. (AnalogicTech) announced the AAT2782 and AAT2783, two new power management ICs (PMICs) for portable applications. Combining two step-down converters with a low VIN LDO, the company claims that these new devices can be used to power both traditional power management functions and noise-sensitive circuits without compromising power efficiency.
"While many portable systems, such as wireless data cards, need a typical 3.3V source to drive a processor, memory or I/O and a lower voltage source to power noise-sensitive circuits, it is very difficult to support those functions at high efficiency with a single PMIC," said Dan Dempsey, Product Line Director for AnalogicTech. "By combining two buck converters with a low VIN LDO and using the LDO to post-regulate the second buck converter, the AAT2782 and AAT2783 extend battery life and reduce board footprint by powering both standard 3.3-V circuits and lower voltage noise sensitive circuits while maintaining high power efficiency"
The AAT2782 and AAT2783 operate off a 2.7 to 5.5V input range and provide three independently regulated dc outputs: two step-down converters and one low input voltage LDO. The two step-down converters on the AAT2782 deliver 1200 and 600mA respectively. On the AAT2783 the two step-down converters supply 1000 and 400mA. On each IC both converters use current mode control to ensure fast transient response and stable operation across the entire operating range. A 1.3 MHz switching frequency supports the use of small external filters.
The low input voltage LDO on both devices is optimized for low noise operation. Designed to operate off a 1.7V input, the LDO delivers up to 400mA with a -80 dB power supply rejection ratio (PSRR) and 65µVRMS output noise with an optional bypass capacitor. The LDO’s output voltage is factory set at 1.2V. The step-down converters on both devices offer high efficiency rates. Using the LDO to post-regulate the output of the second step-down converter for low-noise operation, both devices achieve efficiency levels up to 80%.
The two new PMICs are fabricated in AnalogicTech’s proprietary Modular BCD process. Total quiescent current is 170 µA for the AAT2782 and 135 µA for the AAT2783. Both devices feature 200 µs internal soft start and over-temperature protection.
Qualified across the -40 to +85°C temperature range, the AAT2782 and AAT2783 are available in a Pb-free, 16-pin, TDFN package. The ICs sell for $1.93 and $1.93 respectively in 1K quantities.
