Abstract: VHSIC Hardware Description Language (VHDL) simulation of trapezoidal filtering algorithm was done. The exponentially decaying sequences were considered as the input to the filter. Such kinds of signals are usually obtained after processing (i.e. in analog domain) and digitizing the nuclear detector signals. The trapezoidal filter acts as a pulse shaping filter in a typical nuclear spectroscopy system to optimize the value of ballistic deficit, signal to noise ratio and pulse pile-up losses in order to facilitate improved measurement of time of arrival and energy of radiation particle. The simulation qualifies the algorithm for its implementation in Field Programmable Gate Array (FPGA) for real time applications.