407 of the selected memory cell have settled to their proper voltages they are disconnected from their voltage supplies and are floated the word line which is connected to word gate 402 is then raised and program begins when electrons start to flow from the source bit line to the drain bit line the high che injection efficiency of the twin monos cell of the present invention allows sufficient programming using the energy stored in the high drain voltage bit line without actually dc biasing of the source and drain the word line voltage also limits the extent of bit line equalization because the source bit line will not rise past the voltage of the word line minus the threshold voltage of the word gate which is approximately 0 5v thus after the source bit line rises to 0 5v and the drain bit line falls to 4 5v charge will no longer flow between the two bit lines and so che injection will stop changes in the bit line voltages also affect the voltages of the two floating control gate lines if we assume that the bit line to control gate line coupling ratio is about 30 then a 0 5v bit line voltage change will result in a 0 15 0 3 0 15v control gate line voltage change the bit line and control gate voltages after program has stopped are given in fig8 b in fig8 c the word gate 402.