SWITCHING FREQUENCY OF ADSL POWER SUPPLIES
Power supply’s switching frequency negatively affects the modem’s performance by reducing the number of data bits transmitted in the carrier bands corresponding to the ripple frequency and its harmonics, thereby reducing the modem’s overall data transfer rate. However, there are other power-supply factors that are affected by the switching frequency. Some of these factors include overall supply cost, size, efficiency, and reliability. None of these factors can be optimized independently of the others; and, in many cases, optimizing only one supply parameter leads to a less than optimal overall solution. That is why the power-supply designer must act as a system engineer at the power- supply level, taking into account all design parameters to produce the optimal solution.