Patent ID: 7029239
Filing Date: 2006-04-18
Classification: H05K

Abstract:
1. A system, comprising: a PWM generator configured to generate a PWM (Pulse Width Modulated) signal having a duty cycle dependent on a duty cycle value; and control logic coupled to the PWM generator and configured to generate the duty cycle value to have a piecewise linear relationship with temperature, wherein the piecewise linear relationship is defined by a plurality of linear equations, wherein at least two of a plurality of linear segments defined by the piecewise linear relationship have different slopes; wherein the control logic is further configured to receive a temperature value representing a current temperature and to select one of the plurality of linear equations dependent on which one of a plurality of portions of a temperature range includes the temperature value, wherein the selected one of the plurality of linear equations is associated with the one of the plurality of portions of the temperature range that includes the temperature value; wherein the control logic is further configured to process the temperature value according to the selected one of the plurality of linear equations to generate the duty cycle value; wherein a slope of each of the plurality of linear equations relates a range of PWM duty cycle values generated by that one of the plurality of linear equations to the one of the plurality of portions of the temperature range associated with that one of the plurality of linear equations; and wherein a slope of one of the plurality of linear equations associated with a lower one of the plurality of portions of the temperature range is less than a slope of another one of the plurality of linear equations associated with a higher one of the plurality of portions of the temperature range.