High-Frequency Power in Tunnel Diodes

An expression for high-frequency tunnel-diode power is developed with a simple dissipative load and for signals confined within the nearly linear range of the diode negative resistance. The existence of maximum power output for a given frequency of operation, and for an optimum peak current-to-capacitance ratio is demonstrated. The power and the inductance appear in the equations as a product, and consequently, the higher-power output diodes require the lower inductances. The results are plotted for germanium as well as for gallium arsenide in the form of charts with the ratio of peak current-to-capacity and the operating frequency as coordinates. These charts present two families of curves which cross each other, one referring to constant products of power times inductance and the other referring to constant products of capacity times inductance. The presented data cover a wide operational range of tunnel diodes. For a diode oscillating at 10 kMc and having a resistive cutoff frequency of 30 kMc, the maximum power-inductance product is 0.0224 (mw)(mμh) for a voltage swing of 0.15 volt in the nearly linear range.