Handset TV chipsets powered from a single IC

Edited by the Electronicstalk editorial team Jan 16, 2008

Three-output power ICs are ideal for digital media broadcasting and digital video broadcasting chipsets found in the latest generation of cellphones and PDAs.

Two new devices from Linear Technology combine a 400mA 2.25MHz, synchronous buck regulator with two 150mA LDOs packaged in a 2 x 2mm DFN.

The LTC3672B-1 has a fixed 1.8V output on the switching regulator and fixed 1.2 and 2.8V outputs for the LDOs, whereas the LTC3672B-2 has a fixed 1.2V output on the switcher and fixed 1.8 and 2.8V LDOs.

Both parts are ideal for digital media broadcasting (DMB) and digital video broadcasting (DVB) chipsets found in the latest generation of cellphones and PDAs.

The input voltage range of 2.9 to 5.5V makes them an ideal solution for single-cell Li-ion powered applications.

The 1.2, 1.8 and 2.8V outputs are used to power I/O, memory and core voltages of the latest DMB, DVB processors, as well many standardised DSPs and microcontrollers.

The buck regulator's 2.25MHz switching frequency and the LDO designs enable the use of tiny low-cost externals, providing a very compact footprint for handheld applications.

The LTC3672B's synchronous buck delivers efficiencies as high as 93% and constant frequency, current mode operation minimises noise while offering fast transient response.

The LTC3672B-1's LDOs can be powered from the synchronous switcher's output to maximise efficiency and reduce output ripple.

Other features include internal soft-start and internal compensation.

The LTC3672B-1 and LTC3672B-2 are both available from stock in 8-lead 2 x 2mm DFN packages.

Pricing starts at US $1.95 each in 1000-piece quantities.