Quantance takes in another $12M to improve 4G battery life

Phone power supply maker Quantance has raised another $ 12 million in funding, which the company plans to put to use commercializing its battery-saving envelope tracking technology.

Envelope tracking might sound like a certified mail service, but it’s really a technology used to tame LTE’s normally power hungry ways. LTE is unique among cellular technologies in that its power levels rise and dip dramatically throughout the course of a transmission – think of an LTE signal like the wild crescendos and quiet interludes of classical music.

Envelope tracking closely matches the power fed into the radio with the power needed at given moment to transmit. The result is a highly efficient power supply that can reduce a phone’s power drain by as much as 25 percent over current 4G devices. Given the miserable battery life of first generation of LTE phones, a 25 percent improvement is nothing to scoff at, and once combined with other power-saving technologies such as integrated handset silicon as well as improved batteries, we’ll see phones that can go much longer between charges.

Quantance’s latest $ 12 million round is its Series D with all of its existing investors — TD Fund, Granite Ventures, InterWest Partners and DoCoMo Capital – chipping in. Quantance raised $ 30 million in its previous rounds, going all the way back to 2006, the last of which was an $ 11 million investment in 2011.