A constant-voltage circuit is interposed between a power source and a driver circuit for an electrochromic display. The constant-voltage circuit functions to compensate for variations of an output level of the power source in order to stabilize coloration and bleaching operations. Switching means are...http://www.google.de/patents/US4302751?utm_source=gb-gplus-sharePatent US4302751 - Driver circuit for electrochromic displays
