摘要:
A leak current detection circuit that improves the accuracy for detecting a leak current in a MOS transistor without enlarging the circuit scale. The leak current detection circuit includes at least one P-channel MOS transistor which is coupled to a high potential power supply and which is normally inactivated and generates a first leak current, at least one N-channel MOS transistor which is coupled between a low potential power and at least the one P-channel MOS transistor and which is normally inactivated and generates a second leak current, and a detector which detects a potential generated at a node between the at least one P-channel MOS transistor and the at least one N-channel MOS transistor in accordance with the first and second leak currents.
摘要:
An excluding unit is controlled by a control signal received from a control unit, and based on the control signal a determination is made for each of circuit blocks as to whether either a voltage signal at a position of its corresponding circuit block or a signal indicating a voltage is outputted to a selection unit. From a circuit block which is not in operation, the voltage, but not a voltage signal at a position of the circuit block, is outputted to the selection unit. By this, the circuit block which is not in operation cannot be judged to have voltage drop, and accordingly, a high supply voltage cannot be supplied. Consequently, a malfunction caused by supply voltages to other circuit blocks being too high does not occur.
摘要:
The present invention aims to provide a multi-power supply circuit capable of generating multi-power efficiently and reducing power consumption, and a multi-power supply method therefor. A supply voltage is output from a DCDC converter. Output transistors of linear regulators are series-connected to a power supply path between a resistive element and the DCDC converter. That is, a bias current path is shared between the linear regulators and the corresponding path is taken as one. With the supply voltage as the reference, supply voltages corresponding to intermediate negative voltages between the supply voltage and a reference voltage are generated by the linear regulators. A bias current consumed by the multi-power supply circuit is held constant as a bias current i regardless of the number of the linear regulators.
摘要:
There is provided an oscillator circuit capable of obtaining stable frequency by avoiding output having unstable frequency that is likely to occur to an operation/stop-control-feasible type oscillator circuit when oscillation begins. In such an oscillator circuit, an oscillation permitting signal (EN) sets an oscillator section in oscillation-operable state, whereby a controller section starts operation. The controller section that has stared its operation change an oscillation-frequency control signal (VR) into a signal value corresponding to predetermined oscillation frequency so as to set oscillation frequency at an oscillator section. Further on, the oscillator section outputs an oscillation signal in response to a detection signal (MON) that is outputted after a detector section compares a signal inputted therein with a predetermined signal value and detects that the inputted signal reaches a predetermined signal value. Thereby, transient state of an oscillation-frequency control signal (VR) can be detected. That is, there can be avoided an output of an unstable oscillation signal due to a transient oscillation-frequency control signal (VR).
摘要:
There is provided an oscillator circuit capable of obtaining stable frequency by avoiding output having unstable frequency that is likely to occur to an operation/stop-control-feasible type oscillator circuit when oscillation begins. In such an oscillator circuit, an oscillation permitting signal (EN) sets an oscillator section in oscillation-operable state, whereby a controller section starts operation. The controller section that has stared its operation change an oscillation-frequency control signal (VR) into a signal value corresponding to predetermined oscillation frequency so as to set oscillation frequency at an oscillator section. Further on, the oscillator section outputs an oscillation signal in response to a detection signal (MON) that is outputted after a detector section compares a signal inputted therein with a predetermined signal value and detects that the inputted signal reaches a predetermined signal value. Thereby, transient state of an oscillation-frequency control signal (VR) can be detected. That is, there can be avoided an output of an unstable oscillation signal due to a transient oscillation-frequency control signal (VR).
摘要:
A flash-erasable semiconductor memory device has a memory cell array including a plurality of memory cell transistors each having an insulated floating gate for storing information and a control electrode provided on the floating gate, wherein the flash-erasable semiconductor memory device includes a write control circuit supplied with a write control signal, when writing information. The write control circuit produces a control signal such that a leading edge of the drain control signal appears after a leading edge of the gate control signal. Further, the gate control circuit shuts off the gate control signal such that a trailing edge of the gate control signal appears after a trailing edge of the drain control signal.
摘要:
A flash-erasable semiconductor memory device comprises a memory cell array including a plurality of memory cell transistors each having an insulated floating gate for storing information and a control electrode provided on said floating gate, wherein the flash-erasable semiconductor memory device includes a write control circuit supplied with a write control signal, when writing information. The write control circuit produces a control signal such that a leading edge of the drain control signal appears after a leading edge of the gate control signal. Further, the gate control circuit shuts off the gate control signal such that a trailing edge of the gate control signal appears after a trailing edge of the drain control signal.
摘要:
A nonvolatile semiconductor memory employs sense amplifiers, circuits for providing stabilized source voltages, and circuits for realizing high-speed and reliable read and write operations. The semiconductor memory has a matrix of nonvolatile erasable memory cell transistors. The semiconductor memory employs an arrangement for effectively using a plurality of source voltages and applying a verify voltage to sense amplifiers and word lines, a write verify arrangement for detecting an output of the sense amplifiers, an arrangement for comparing an output of the sense amplifiers with a reference value to determine whether or not a written state of the memory cell transistors is acceptable, an arrangement for adjusting an output of the sense amplifiers with use of inverters and transistors in response to a current flowing to the memory cell transistors, to improve a drive speed of the sense amplifiers, an internal source voltage generating arrangement using an n-channel depletion transistor connected to an external source voltage (Vcc), the gate of the transistor being connected to a low source voltage (Vss) to provide an internal source voltage (Vci), a combination of an arrangement for dropping the external source voltage (Vcc) for read to a predetermined value to drive a read circuit in the memory and an arrangement for dropping an external voltage (Vpp) for write, to generate a word line potential for a verify-after-write operation, an arrangement for setting a reference voltage (Vref) as a lower threshold (Vth) allowed for cell transistors (11.sub.00 to 11.sub.22), and comparing the voltage of a data bus (13) with the reference voltage (Vref), to simultaneously carry out an erase-verify operation on all memory cell transistors, and a pre-read arrangement for accessing the next address during a read time of the sense amplifiers, to improve a read speed.
摘要:
A layout method of decoupling capacitors while ensuring the decoupling capacitance necessary for each grid area. The method includes calculating the total power consumption of logic cells, arranging the decoupling capacitance throughout the subject area in correspondence with the total power consumption, dividing the subject area into a plurality of grid areas, arranging the logic cells in each grid area, determining whether the decoupling capacitance is sufficient in each grid area for the logic cells in that grid area, and performing a supplementing process of the decoupling capacitance based on whether the decoupling capacitance is sufficient.
摘要:
A semiconductor device includes both a logic circuit and a macro circuit. The macro circuit includes a circuit that consumes direct current (DC). In order to conserve power and allow for testing, the consumption of DC by the current consumption circuit can be stopped with a stop signal, which stops the operation of the macro circuit. The macro circuit can be restarted or returned to normal operation mode without risk of error caused by the stopping of the macro circuit.