Samsung Electronics Co., Ltd.

Myoung-Kyu Seo

Sang-Won Kim

Tae-Seong Kim

Jong-Hoon Jung

Geum-Jong Bae

In-Wook Cho

Myung-Yoon Um

Byoung-jin Lee

Jin-hee Kim

Hoon-Jin Bang

Hyo-Sang Lee

Geon-Woo Park

A word line driving circuit includes a read voltage generator and a word line driver. The read voltage generator precharges a clamp capacitor with a power supply voltage to stably generate a read voltage in response to a read command. A capacitance of the clamp capacitor is varied to compensate for a fluctuation of a power supply voltage level. The word line driver distributes electric charges precharged in the clamp capacitor to a word line in response to a word line selecting signal. Therefore, the word line driving circuit reduces unnecessary power consumption in a standby mode by operating the word line rapidly with charge sharing in a read mode.

Circuit and method of driving a word line by changing the capacitance of a clamp capacitor to compensate for a fluctuation of a power supply voltage level

Erasure methods for a nonvolatile memory cell that includes a gate electrode on a substrate, source and drain regions in the substrate at respective sides of the gate electrode, and a charge storage layer interposed between the gate electrode and the substrate. A nonzero first voltage is applied to the source region starting at a first time. While continuing to apply the first nonzero voltage to the source region, a second voltage having an opposite polarity to the first voltage is applied to the gate electrode starting at a second time later than the first time. The second voltage may increase in magnitude, e.g., stepwise, linearly and/or along a curve, after the second time.

Soft erasing methods for nonvolatile memory cells

Provided are a program control circuit for flash memory devices and a control method utilizing such a circuit for controlling the bit line voltage level during programming operations for flash memory devices that include memory cells arranged in the form of a matrix, in which each of the memory cells is connected to a word line, a bit line, and a source line and which provides a program current to the bit line. The program control circuit includes a voltage level sensing control portion, a switching control portion, a current sink and a switching circuit. The voltage level sensing control portion is enabled or disabled in response to a first program control signal and compares the voltage of a bit line connected to a memory cell being programmed with a reference voltage and outputs a voltage control signal corresponding to the result of the comparison. The switching control portion outputs a switching bias signal in response to the voltage control signal and a second program control signal. The current sink provides a predetermined current to a ground voltage in response to a reference bias signal. The switching circuit, which is connected between the bit line and the current sink, is turned on or off in response to the switching bias signal.

Flash memory program control circuit and method for controlling bit line voltage level during programming operations

Growing community of inventors

Suwon-si, South Korea

Myoung-Kyu Seo