Patent attributes
A programmable ROM includes first and second field effect transistors serially connected between first and second power source terminals, a third field effect transistor having a gate connected to a word line and used for data transfer between a first bit line and the drains of the first and second field effect transistors, fourth and fifth field effect transistors serially connected between the first and second power source terminals, and a sixth field effect transistor having a gate connected to the word line and used for data transfer between a second bit line and the drains of the fourth and fifth field effect transistors. The threshold voltages of the first and fourth field effect transistors are different from each other and the magnitude relation thereof is determined according to ROM data.
