Fairchild Releases RF Power DC-DC Converter For W-CDMA/CDMA RFPAs In 3G Handsets
Fairchild Semiconductor is claiming that it is providing the industry’s smallest power management solution for the designers of 3G handsets and wireless datacards. The FAN5902, RF power dc-dc converter, is packaged in a 12 bump, 0.5mm pitch CSP package and operates at 6MHz with a reduced size 0.5µH chip inductor, saving space and component costs.
The converter helps to extend talk-time by up to 40 minutes in 3G handsets by adapting the voltage supply level of the 3G RF power amplifier according to the RF power sent through the antennae, enabling higher power efficiency for a wide range of antenna power levels. This results in up to 100mA of battery current consumption savings in data-centric and smart phones especially in suburban and poor coverage areas. This feature enables 20 to 30% more power, dramatically extending connection time and allowing 3G handsets to run more processor applications.
In addition, the FAN5902 offers up to 800mA rms current output capability to service excessive RF PA current resulting from strong antenna mismatch and a 50mΩ on resistance bypass FET, enabling operation down to 2.7V.
The FAN5902 also addresses the key problem of overheating in the RF power amplifier, especially at high battery voltage. Since the FAN5902 scales down the RFPA supply voltage, reducing its heating by 20 to 40%, the heat sink can be shrunk and the component density can be increased, reducing weight, cost and size.
The units are priced (each, 1000 pieces) at US $0.75.
