Sunnyvale, Calif., USA:

Power supplies for GSM phone baseband chipsets must rapidly ramp from a few milliamps to full load. Needless to say, then, designers deem an extremely fast transient response as critical.

Advanced Analogic Technologies’ (AnalogicTech) recent innovation hopes to fill that need. Its series of specifically designed dc-dc converters offer very fast transient response, suiting them for portable systems powered by single-cell lithiumion/polymer batteries.

These step-down converters provide an input voltage range of 2.7 to 5.5V and output levels down to 0.6V. The devices deliver up to 400mA of load current and maintain a no-load quiescent current of just 27
A.

The AAT2512 is a dual-channel synchronous buck converter operating over the same 2.7 to 5.5V input range. Each regulator features independent input and enable pins. Every channel delivers 400mA of load current, and the device supports quiescent current levels of 27
A for light load conditions.

Both the AAT1146 and the AAT2512 come in fixed or programmable versions, with up to 98% efficiency. The devices use a high, 1.4MHz typical switching frequency to minimise the size of external components and keep switching losses low.