摘要:
Disclosed is an art making it possible that, in a reference cell circuit for outputting a plurality of different reference level signals, even if the number of transistors serving as reference cells and each having a floating gate increases, the time required for setting channel currents of the transistors will not increase. The floating gates of a plurality of transistors for generating different reference signal levels are connected in common so that the channel currents of all the transistors can be set simultaneously. The transistors have the channel lengths thereof, channel widths thereof, or both of them made different. The channel currents of the transistors are therefore mutually different. An error in all reference levels dependent on a manufacturing process is compensated for by adjusting an amount of charge to be injected into the floating gates.
摘要:
An object of the present invention is to provide a semiconductor device that permits easy and efficient testing. A nonvolatile semiconductor memory comprises word lines WLi and bit lines BLi, a memory cell matrix 17 consisting of nonvolatile memory cells Cij, a sense amplifier 15, a write/erase timing circuit 9 for performing timing control necessary for write and erase operations, and a status register 2 for storing the operating state of the memory at the completion of the operation of the circuit 9, wherein there are provided, outside the address of the memory cell matrix 17, two kinds of dummy cells, D1, D2, D3, . . . , whose values are fixed to different values that induce different outputs from the sense amplifier 15. A pass condition or a fail condition is generated by accessing the dummy cells.
摘要:
An object of the present invention is to provide a semiconductor device that permits easy and efficient testing. A nonvolatile semiconductor memory comprises word lines WLi and bit lines BLi, a memory cell matrix 17 consisting of nonvolatile memory cells Cij, a sense amplifier 15, a write/erase timing circuit 9 for performing timing control necessary for write and erase operations, and a status register 2 for storing the operating state of the memory at the completion of the operation of the circuit 9, wherein there are provided, outside the address of the memory cell matrix 17, two kinds of dummy cells, D1, D2, D3, . . . , whose values are fixed to different values that induce different outputs from the sense amplifier 15. A pass condition or a fail condition is generated by accessing the dummy cells.
摘要:
A semiconductor memory having a non-volatile semiconductor memory cell, wherein the depletion of electrons from the semiconductor memory cell takes place in conjunction with the depletion of electrons from a load transistor so that a voltage difference between each threshold voltage can be maintained at the same level, and a writing operation is performed in a configuration where the load transistor of the non-volatile semiconductor memory cell is equipped with, like the non-volatile semiconductor memory cell, a floating gate, so that an initially stored memory content of the semiconductor memory cell can be read out.