Patent ID: 6346900
Filing Date: 2002-02-12
Classification: G09G,H03M

Abstract:
A circuit for outputting one of first and second analog voltages in first and second voltage ranges, respectively, the first voltage range being within a range from a high voltage V1 to a low voltage V2, the second voltage range being within a range from a high voltage V3 to a low voltage V4, comprising:a first digital-to-analog converter coupled to receive a first digital input signal corresponding to the first voltage range; a second digital-to-analog converter coupled to receive a second digital input signal corresponding to the second voltage range; an output terminal; a first gating circuit coupled between an analog output of the first digital-to-analog converter and the output terminal; a second gating circuit coupled between an analog output of the second digital-to-analog converter and the output terminal; wherein when the first digital input signal has a magnitude corresponding to the first voltage range and the second digital signal has a magnitude causing the output of the second digital-to-analog converter to render the second gating circuit nonconductive, the first analog voltage is output by the first digital-to-analog converter on the output terminal; and wherein when the second digital input signal has a magnitude corresponding to the second voltage and the first digital signal has a magnitude causing the output of the first digital-to-analog converter to render the first gating circuit nonconductive, the second analog voltage is output by the second digital-to-analog converter on the output terminal.