Abstract: To rescue the low voltage failure of self-destruction circuit of fuze, an improved analog circuit using discrete components was proposed, which was based on energy balance. By strictly limiting input terminals' voltage of the comparator, full charge of the capacitor used for detonating was achieved in a low charging voltage; energy consumption modeling was completed and the time of self-destruction was designed accurately; using the Monte Carlo method, the influence of components tolerance on the characteristics of the circuit was analyzed. The simulation shows that detonating threshold can be reduced to 4.5V, relative deviation of self-destruction time is under 1% and the circuit is reliable under the voltage range of 5.5V to 15.0V.