In an RF communication system, aspects of constant or proportional to absolute temperature biasing for minimizing transmitter output power variation may comprise configuring at least one current source to provide a temperature dependent current, where the current may be constant with temperature or vary proportionally to absolute temperature. A control voltage that may be generated by an operational amplifier may be fed back to control the current source. An input reference voltage may also be generated for the operational amplifier by utilizing PN junction characteristics of at least one bipolar junction transistor. Resistance may be adjusted to allow operation of the current source at a plurality of different supply voltages, including the different supply voltages that may be less than 1.2 volts, for example. Additionally, adjusting the resistance may also allow the current to be constant with temperature or vary with temperature.