European mobile phone firms are looking at techniques for designing mini solar panels into handsets to extend standby times to a week or more.
Specific unnamed handset firms have projects in place looking at how to incorporate small 50mm solar cells working in parallel with battery cells to extend the time between recharges.
“Handset firms in Europe have approached us about designs for solar cells,” said Uwe Mengelkamp, director of DC-DC converters at Texas Instruments.
There is no question of a solar cell powering the handset alone, due to the size limitations, but according to Mengelkamp, it is feasible that a cell less up to 25cm sq in area could produce a charge current of 11mA which could be used in parallel with the battery cells to extend standby time of the handset.
The aim is to increase the standby time of the more power hungry multimedia phones to week.
“There is a lot of research going into this,” said Mengelkamp.
Handsets with mini solar cells could be on the market within two years. “In a way we are in a similar position with this to where we were when we introduced a driver ICs to support OLED displays two years ago,” said Mengelkamp.
“Designers including those in wireless and portable audio fields are looking at how to apply solar and fuel cell technology to extend battery life. It is not certain what we will see first,” said Mengelkamp, who made the comments as TI launched a DC-DC converter with a very low start-up voltage which is designed to work with solar and fuel cells in portable systems.