Abstract: In a splitterless xDSL communications services set-up providing data and voice services to co-connected equipment, data signals may cause audible interference in POTs handsets. The degree of the interference varies widely due to a wide variation of customer tolerance and of susceptibility of the handsets. Reducing data channel transmission power during an off-hook event may reduce interference. A method and system are provided for user adjusted cutback. While making a POTs call, data channel power may be adjusted until acceptable performance is obtained. The customer selected power cutback influences both ATU-R and ATU-C transmit levels.

Abstract: A variable power supply technique for use with a high efficiency line driver uses a signal peak amplitude to determine a start of a rise time for a power supply to begin supplying operating voltage to the line driver. This ensures that the voltage supplied to the line driver essentially tracks the output signal. A slew start delay circuit detects when the signal rises above a level that can be supported by a current power supply, and determines a variable delay for switching on a power supply to supply a higher voltage to the line driver. The advantages include reduced power usage, less heat dissipation, and the ability to select a primary power supply that outputs a lower voltage.