Different GaAs HBT ESD diode configurations are analyzed and compared using human body model (HBM) and transmission line pulse (TLP) measurements. A common diode stack test circuit consisting of 3 series forward and reverse diodes is used to analyze ESD ruggedness dependence on layout and area. Both base emitter and base collector junction ESD ruggedness is compared and analyzed. To our knowledge, this is the first time data has been presented for GaAs HBT diodes that calculates the ratio of HBM voltage to maximum TLP current