(A) 512-bit mask programmable ROM using PMOS technology

Abstract

A 512-bit Mask Programmable ROM has been designed and fabricated using PMOS technology. The content of the memory was written through the gate pattern, and was checked by displaying the output of the chip on an oscilloscope with 512 matrix points consisting of 32 columns and 16 rows. The operation of the chip was successful with operating voltage from -6V to -12V, maximum power consumption of 27 mW and maximum propagation delay of 13 μsec. The output of the chip was capable of driving the input of a TTL gate directly and retained a high impedance state when the chip select function disabled the output.