Patent ID: 6210008
Filing Date: 2001-04-03
Classification: B60R

Abstract:
A vehicular electrochromic rearview mirror system, comprising:at least one electrochromic rearview mirror assembly having an electrochromic reflective element, said electrochromic reflective element assuming a partial reflectance level in response to a signal applied thereto;a drive circuit applying a drive signal to said electrochromic reflective element establishing a partial reflectance level thereof, said drive circuit including a digital controller and a switching power supply controlled by said digital controller producing said drive signal;wherein said switching power supply comprises an impedance device and at least one electronic switch in series electrical connection between said electrochromic reflective element and a voltage potential, and another electronic switch between said impedance device and another voltage potential to conduct current in said impedance device when said at least one electronic switch is not conducting.