Title:
【発明の名称】自動車ダッシュボードライト制御
Document Type and Number:
Japanese Patent JP2002529294
Kind Code:
A
Abstract:
Dashboard dimmer light circuit for a vehicle, for example a car or truck. A power supply 10 provides a step-function voltage signal to an op-amp oscillator circuit 20 which provides a triangular voltage oscillation signal to an op-amp level comparator 40 which, in turn, compares the triangular voltage oscillation signal to a voltage reference for providing a pulse-width-modulated (PWM) voltage signal to a power FET driver 70 which, in turn, responds to the pulse-width-modulated voltage signal by providing a current signal to an automobile dashboard dimmer light 80. Features of the invention include a) a dashboard dimmer light having a stable oscillator frequency, b) PWM duty cycle stability in a dashboard dimmer light, c) efficient accomplishment of the invention's oscillator and level comparator functions within a single IC, d) reduction of electromagnetic interference which might otherwise intefere with other electronic equipment in the dashboard.
Inventors:
Thomas Jay Wand
Application Number:
JP2000580053A
Publication Date:
September 10, 2002
Filing Date:
September 22, 1999
Export Citation:
Assignee:
Meso-electronics Incorporated
International Classes:
B60Q3/04; G05B11/28; G05F1/56; H05B39/04; (IPC1-7): B60Q3/04
Attorney, Agent or Firm:
Masatake Shiga (7 outside)