Power Amplifier Savings with DC-DC Converters in GSM-GPRS-EDGE Mobile Handsets
In the last decade, mobile phones have become an integral part of our life. Up to one billion new mobile phones are shipped each year by manufacturers. Newly introduced features and smaller form factors of mobiles require less current consumption from a battery. Battery technologies are getting more advanced, allowing higher capacity with a smaller size. Semiconductor technologies are going to smaller geometries, which results in less consumption for base-band circuitry of a mobile. But analog circuits (and especially RF) are still remaining power hungry. One of the most critical components is the RF power amplifier (PA), which consumes a high portion of the energy from a battery. Appropriate standards facilitate extending the battery life between recharges, by introducing transmit power control mechanisms, which, at the same time, are managing the RF spectrum noise requirements, allowing more users to talk simultaneously, with better voice quality. Mobile designers introduce proprietary mechanisms of power management inside a handset to be competitive. The most widespread mobile network in the globe is based on GSM-GPRS Standard. EDGE modulation added to this Standard allows an increase in the data rate of a transmit signal, which results in more users able to talk simultaneously and convey more data through a network.