BJT Half Supply Voltage Generator

BJT half supply voltage generator for driving loads having moderate impedance. R1 and R2 are equal, the value is adjusted based on the load resistance. These two resistors must be low enough so that the current to the base of the transistor is negligibly small and the current through them (R1 and R2) are approximately equal. However, they must not be too low that the power they dissipate is unnecessarily high.