Abstract: A memory device, such as a 3D AND flash memory, includes a memory cell block, a word line driver, and a plurality of bit line switches. The word line driver has a plurality of complementary transistor pairs for respectively generating a plurality of word line signals for a plurality of word lines. Substrates of a first transistor and a second transistor of each of the complementary transistor pairs respectively receive a first voltage and a second voltage. Each of the bit line switches includes a third transistor. A substrate of the third transistor receives a third voltage. The first voltage, the second voltage, and the third voltage are constant static voltages during a soft program operation and a soft program verify operation.

Abstract: A compound screwdriver head, which comprises a first working portion and a second working portion of the same size, the first, second working portion of the bigger size is used for screwing and unscrewing a bolt of bigger, smaller size respectively, so that different sizes of bolts can be locked and unloaded by one screwdriver. Thereby this invention is not only can save the structure of the bolt, but also can prolong the life of the bolt.

Abstract: A compound screwdriver head, which comprises a first working portion and a second working portion of the same size, the first, second working portion of the bigger size is used for screwing and unscrewing a bolt of bigger, smaller size respectively, so that different sizes of bolts can be locked and unloaded by one screwdriver. Thereby this invention is not only can save the structure of the bolt, but also can prolong the life of the bolt.