A direct current to pulse amplitude modulated (“PAM”) current converter, denominated a “PAMCC”, is connected to an individual source of direct current. The PAMCC receives direct current and provides pulse amplitude modulated current at its output. The pulses are produced at a high frequency relative...http://www.google.fr/patents/US7719864?utm_source=gb-gplus-shareBrevet US7719864 - Pulse amplitude modulated current converter
