摘要:
Disclosed herein is a non-volatile semiconductor memory device comprising a mode signal output means for outputting a mode signal for conducting flash programming or flash erasing, a group selection signal output means for outputting a group selection signal for selecting a row decoding group, a first selection means for selecting the row decoding group controlling the word line in accordance with 10 the group selection signal, and a second selection means selecting the word line corresponding to the memory cell from a plurality of the word lines controlled by the row decoding group selected by the first selection means. In the present inventions the time required for the flash programming and the flash erasing can be reduced without the addition of a further element and the chip areas can be reduced.
摘要:
A power source circuit for a flash memory includes a positive circuit section for generating a positive voltage source, a source follower transistor for converting the impedance of the first voltage source, a negative circuit section for generating a negative voltage source while maintaining a voltage difference between the output of the source follower transistor and the negative voltage source at a first reference potential. The positive circuit section includes a voltage compensating transistor having a threshold voltage equal to the threshold of the source follower transistor.
摘要:
A semiconductor memory device comprises a plurality of sub bit lines 12a and 12b to which a plurality of memory cell transistors 13a through 13h are connected. The sub bit lines are selectively connected to a main bit line 11a. The sub and main bit lines are made of metallic material.
摘要:
A semiconductor device has a plurality of power supply circuits whose generated voltages are different from each other, and a plurality of internal circuits whose operating voltages are different from each other. The power supply circuits and the internal circuits are interconnected by power lines with respective power supply switches inserted therein. The power lines are connected to a single external terminal by respective control lines with respective external switches inserted therein. The power supply circuits and the internal circuits can be tested from the single external terminal.
摘要:
A fuse data read circuit includes a fuse data holding unit which holds fuse data, a fuse data read unit which detects fuse data, and a bias voltage generating circuit which generates a bias voltage. The fuse data read unit includes a current mirror circuit and a control circuit provided between the current mirror circuit and the fuse data holding unit. The bias voltage generating circuit applies the bias voltage to the control circuit.
摘要:
A semiconductor memory device of the present invention has a write circuit and bit line coupled to the write circuit. Output from the write circuit is sent to corresponding bit line by a transfer gate. During data write term, a write voltage is applied to the bit line when writing a "0" and zero volts is applied to the bit line when writing a "1". The bit line therefore is not left in a floating state when writing either a "0" or a "1". A rise in voltage potential of a bit line due to noise is prevented from occurring, thereby eliminating data writing errors.
摘要:
A checkerboard data pattern is written in a semiconductor memory with a simple arrangement. First, memory cell transistors M00-M77 are erased. A test signal TS is turned to "L," an address ax0 to "1," write signals D0, D2, D4 and D6 to "1." This causes "1" to be written in the memory cell transistors even-numbered in both the rows and columns. Then, the test signal TS is turned to "L," an X address ax0 to "0," write signals D1, D3, D5 and D7 to "1." This causes "1" to be written in the memory cell transistors odd-numbered in both the rows and columns. Thus, the checkerboard can be written with a simple arrangement by activating only the least significant bit ax0 of X addresses ax2-ax0.
摘要:
The present invention provides a semiconductor device with small space factor, which controls the application of voltages higher than a power supply voltage to internal circuits. This device includes a first transistor provided with a semiconductor substrate of one conductive type, a first region of second conductivity type formed in the semiconductor substrate, a second region of the second conductivity type formed independent of the first region, a third region of the first conductivity type formed in the first region, and a fourth region of the first conductivity type formed in the first region independent of the third region, having the first region as its back gate, and a second transistor provided with a fifth region of the first conductivity type formed in the second region and a sixth region of the first conductivity type formed in the second region independent of the fifth region, having the second region as its back gate, wherein a back gate bias voltage higher than the power supply voltage applied to the second region is applied to the first region.
摘要:
An analog-to-digital converter comprises the following elements. A reference voltage generation circuit is provided for dividing a reference voltage into a plurality of divided reference voltages having voltage levels different from each other. A plurality of comparators are provided, each of which has a first input terminal connected to an analog input line for fetching analog signals and a second input terminal connected to the reference voltage generation circuit for fetching a corresponding one of the divided reference voltages so as to compare the analog signals with the divided reference voltage. Each of the comparators has an output terminal through which an output digital signal is outputted. The comparators are connected to any one of a plurality of pairs of different power supply lines and different ground lines, wherein the different power supply lines are separated from each other as well as the different ground lines are separated from each other so that no interference between the different power supply lines and between the different ground lines appears through any noise generated on any of the comparators. A decoder circuit is connected to the output terminals of the comparators for fetching the compared digital signals and decoding the compared digital signals.
摘要:
A constant voltage generating circuit comprises a charge pump circuit for generating a high voltage on a high voltage output terminal, a clamp circuit having a P-channel MOSFET having a drain and a gate interconnected to each other and a source connected to the high voltage output terminal and an anode-grounded zener diode having a cathode connected to the drain of the P-channel MOSFET. A charge detecting circuit generates a charge detection signal when the amount of electric charge having flowed through the clamp circuit reaches a predetermined value. A clock control circuit includes a RS flipflop reset by a reset signal and set by the charge detection signal, and operates to stop application of a clock signal to the charge pump circuit on the basis of an output of the RS flipflop.