Method and apparatus for error compensation using a non-linear digital-to-analog converter

摘要

A non-linear digital-to-analog converter (non-linear "DAC") and method are disclosed for scaling a digital input value by a non-integer and producing an analog output. The digital input value is multiplied by a non-integer, and the integer portion of the result is fed to a linear DAC to produce a linear analog output. At least one of the bits of the integer portion of the result is decoded, and at least one compensation value is generated responsive to the decoding. The compensation value is added to the linear analog output and represents the fractional portion of the result of scaling the digital input value by the non-integer. A method is also disclosed for utilizing the non-linear DAC for error compensation in a computer graphics system. Color intensity values are scaled up by a non-integer greater than one. A first analog output is generated proportional to the integer portion of the result. At least one bit of the integer portion of the result is decoded, and a second analog output is generated responsive to the decoding. The second analog output represents the fractional portion of the result. The first and second analog outputs are combined, and the combined analog output is used to drive a display device.