Brain Power

by Rahul Sarpeshkar IEEE Spectrum Online, May 2006 A team of researchers at the Massachusetts Institute of Technology have finished work on a tiny bionic ear processor that can be powered by a 2-gram battery that requires a wireless recharge every two weeks. The development signals the beginning of making low-power circuits that have the ability to restore hearing in deaf people, according to the lead researcher, an associate professor of electrical engineering at MIT. The researchers used a microphone and preamplifier to transform sound into an analog signal transmitted to the listener through an automatic gain-control circuit, which lessens the range of intensity. Then, a 16-channel spectrum analyzer distributes the signal into frequency components, delaying digitization until the signal has been computed by the circuit. This allows for the intensity of the current to be controlled, leaving more power for stimulating the nerves. Read more