Control circuit for radio frequency power of cellular phone

A controller is designed to set Rf power levels easily and to extend the number of levels for mobile phone system. Also this is stable enough to sustain power levels under even harsh environments. The controller features the first voltage supply Vd connected to Vcc through variable resistor (VR1), ground level source Vs, switching circuit (1) giving selective output of Vd and Vs utilizing minimum 4 bits logic signal from the logic controller (MAc) in cell site, resistances (R1-R5) for combinational RF output voltage V0, and Abc circuit composed of comparator amplifier (2) and power amplifier (4) with additional modulating signal.