Battery Life in 2G, 3G and 4G LTE Maximized by TI's First Power Circuits with MIPI RFFE

On Monday, August 26, 2013, Texas Instruments (TI) introduced the first radio frequency (RF) power converters that integrate the MIPI Alliance’s RF front end (RFFE) digital control interface. This is a specification that simplifies multi-band and multi-radio communications.

A buck converter is a step-down DC to DC converter. Its design is similar to the step-up boost converter. Similar to the boost converter it is a switched-mode power supply that uses two switches, an inductor and a capacitor.

The easiest way to reduce the voltage of a DC supply is to use a linear regulator, but linear regulators waste energy as they operate by dissipating excess power as heat. Buck converters, on the other hand, can be 95 percent efficient, or higher for integrated circuits. This makes them useful for tasks such as converting the main voltage in a computer down to the 0.8-1.8 volts needed by the processor.

TI’s LM3263 buck converter and LM3279 buck boost converter significantly reduce the heat and power consumption in RF power amplifiers. This improves battery life and extends talk time in 2G, 3G and 4G LTE smartphones, tablets and data cards. By regulating the power consumption and using higher voltage output only when needed the battery can hold its charge allowing for the extended talk times.

As listed by Texas Instruments, some of the key features and benefits of the LM3263 and LM3279 are:

• MIPI RFFE digital control interface provides compatibility with next-generation RF front end chipsets, power amplifiers and reference platforms. The 2.5-A LM3263 meets voltage and current requirements of 2G, 3G and 4G, and the LM3279 supports 1-A loads for 3G and 4G
• Smallest solution size: The 2.7-MHz LM3263 buck converter results in a 10-mm2 total solution size; and the LM3279 is a 13-mm2 solution
• Extends battery run-time: 95-percent efficiency; reduces heat dissipation and cuts battery current consumption through average power tracking with dynamically adjustable output voltage
• High performance, low noise: Designed to meet RF and 3GPP requirements, the LM3279 buck-boost supports high linearity and high output power, even at low battery voltages

To complement the buck converters, TI has also introduced the LM335. It is a general output expander with MIPI RFFE host interface. The LM335 reduces the general purpose input/output pin allocation giving designers more flexibility to support up to eight additional analog outputs that use analog-controlled, non-MIPI RFFE compliant components.

This week, August 27-29, 2013, our very own Mobility Tech Zone is hosting the Super Wi-Fi Summit in Las Vegas. Among so many others, Peter Flynn, product and program manager at Texas Instruments will be there. It’s not too late to drop by.