| 摘要 |
PURPOSE: To provide a voltage generating circuit capable of preventing the threshold distribution of a memory cell from being spread by a temperature change in a flash memory. CONSTITUTION: This voltage generating circuit is provided with current source 1 and 2 for generating a fixed current which does not fluctuate with a temperature, current sources 3 and 4 for generating a current proportional to the temperature, MOS transistors PA1, PA2, NA1 and NA2 and a resistor Rout. While selectively using the respective current sources by supplying enable signals EN1b, EN2, EN3b and EN4 to the gates of the said respective MOS transistors, both positive and negative temperature characteristics are variously controlled. By generating a control gate voltage at the time of read or verify read in this voltage generating circuit, the fluctuation of a memory cell current caused by the temperature can be always eliminated irrespectively to read time. Further, by eliminating the temperature dependency of a read current, threshold distribution range can be made narrow.
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