Abstract:
A semiconductor memory device comprising: an array of memory cells; an address input circuit for receiving an external address in response to an address clock signal; a selecting circuit for selecting a memory cell in response to an address output from the address input circuit; a data output circuit for outputting the data read out from the selected memory cell in response to first and second data clock signals; and an internal clock generating circuit for generating the address clock signal and the first and second data clock signals in response to an external clock signal and a complementary clock signal thereof, wherein the address clock signal and the first and second data clock signals have twice the frequency (or half the period) of the external clock signal when in a test mode.
Abstract:
Provided is an amplifier circuit having a constant output swing range and a stable delay time, where the amplifier circuit includes a first bias unit, a second bias unit, a comparison unit, and an amplifier unit, and the first bias unit responds to an internal reference signal with a predetermined voltage level and maintains constant the amount of a first current, and the second bias unit receives an external reference signal, responds to a control voltage, and controls the amount of a second current to be the same as the amount of the first current, and the comparison unit compares a voltage level of a first node with a voltage level of a second node, and controls a voltage level of the control voltage according to the comparison result, and the amplifier unit compares a voltage level of an external input signal with a voltage level of the external reference signal, amplifies and outputs a voltage difference between the two compared signals, responds to the control voltage, and controls the amount of a third current to be the same as the amount of the first current although the level of the external reference signal is varied, such that the amplifier circuit and a circuit for receiving data can maintain a constant output swing range and a stable delay time irrespective of variations in the voltage levels of the external input signal or the external reference signal.
Abstract:
An apparatus for generating an internal clock signal for acquisition of accurate synchronization is provided. The apparatus including: an input buffer for buffering the external clock signal to output a first reference clock signal; a delay compensation circuit for delaying the first reference clock signal; a forward delay array; a mirror control circuit comprising a plurality of phase detectors for detecting delayed clock signals synchronized with a second reference clock signal; a backward delay array; and an output buffer to generate an internal clock signal. An internal clock signal in accurate synchronization with the reference clock signal can be generated by minimizing the delay and distortion of the reference clock signal.
Abstract:
Provided is an amplifier circuit having a constant output swing range and a stable delay time, where the amplifier circuit includes a first bias unit, a second bias unit, a comparison unit, and an amplifier unit, and the first bias unit responds to an internal reference signal with a predetermined voltage level and maintains constant the amount of a first current, and the second bias unit receives an external reference signal, responds to a control voltage, and controls the amount of a second current to be the same as the amount of the first current, and the comparison unit compares a voltage level of a first node with a voltage level of a second node, and controls a voltage level of the control voltage according to the comparison result, and the amplifier unit compares a voltage level of an external input signal with a voltage level of the external reference signal, amplifies and outputs a voltage difference between the two compared signals, responds to the control voltage, and controls the amount of a third current to be the same as the amount of the first current although the level of the external reference signal is varied, such that the amplifier circuit and a circuit for receiving data can maintain a constant output swing range and a stable delay time irrespective of variations in the voltage levels of the external input signal or the external reference signal.
Abstract:
A synchronous mirror delay circuit comprises a delay monitor circuit for delaying a reference clock signal from a clock buffer circuit. A forward delay array sequentially delays an output clock signal of the delay monitor circuit to generate delay clock signals, and the mirror control circuit detects a delay clock signal synchronized with the reference clock signal among the delay clock signals. A backward delay array delays a clock signal delayed by the mirror control circuit, and a clock driver receives an output clock signal of the backward delay array to generate the internal clock signal. A locking range control circuit controls a delay time of each clock signal transferred to the delay monitor circuit by the amount of a delay time of each signal transferred to the clock driver when none of delay clock signals of the forward delay array is synchronized with the reference clock signal.
Abstract:
Provided is an amplifier circuit having a constant output swing range and a stable delay time, where the amplifier circuit includes a first bias unit, a second bias unit, a comparison unit, and an amplifier unit, and the first bias unit responds to an internal reference signal with a predetermined voltage level and maintains constant the amount of a first current, and the second bias unit receives an external reference signal, responds to a control voltage, and controls the amount of a second current to be the same as the amount of the first current, and the comparison unit compares a voltage level of a first node with a voltage level of a second node, and controls a voltage level of the control voltage according to the comparison result, and the amplifier unit compares a voltage level of an external input signal with a voltage level of the external reference signal, amplifies and outputs a voltage difference between the two compared signals, responds to the control voltage, and controls the amount of a third current to be the same as the amount of the first current although the level of the external reference signal is varied, such that the amplifier circuit and a circuit for receiving data can maintain a constant output swing range and a stable delay time irrespective of variations in the voltage levels of the external input signal or the external reference signal.
Abstract:
Disclosed is a synchronous mirror delay circuit for generating an internal clock signal synchronized with an external clock signal, comprising: a clock buffer circuit that generates a reference clock signal in response to the external clock signal; a delay monitor circuit that delays the reference clock signal; a forward delay array for delaying an output clock signal of the delay monitor circuit to generate delay clock signals; a mirror control circuit that receives the delay clock signals and the reference clock signal to detect one delay clock signal synchronized with the reference clock signal among the delay clock signals; a backward delay array that delays the delay clock signal detected by the mirror control circuit to output a synchronous clock signal; a delay circuit that delays an asynchronous clock signal output through the forward delay array; and a clock driving circuit that outputs the delayed asynchronous clock signal as the internal clock signal when the reference clock signal is not synchronized with one of the delay clock signals.
Abstract:
An internal clock generating circuit of a semiconductor device includes: a delay chain having a plurality of delay units for generating multi-phase clocks by adjusting an input clock; a thermometer for outputting a thermometer code value in response to an input selection data; a multiplexer for selectively outputting one of a plurality of clocks input from the delay chain in response to the thermometer code value of the thermometer; and a pulse regenerator for outputting an adjusted internal clock by restoring a pulse form of the clock output from the multiplexer into its original state and controlling the delay thereof as much as desired.
Abstract:
An apparatus for generating an internal clock signal for acquisition of accurate synchronization is provided. The apparatus including: an input buffer for buffering the external clock signal to output a first reference clock signal; a delay compensation circuit for delaying the first reference clock signal; a forward delay array; a mirror control circuit comprising a plurality of phase detectors for detecting delayed clock signals synchronized with a second reference clock signal; a backward delay array; and an output buffer to generate an internal clock signal. An internal clock signal in accurate synchronization with the reference clock signal can be generated by minimizing the delay and distortion of the reference clock signal.
Abstract:
Provided is an amplifier circuit having a constant output swing range and a stable delay time, where the amplifier circuit includes a first bias unit, a second bias unit, a comparison unit, and an amplifier unit, and the first bias unit responds to an internal reference signal with a predetermined voltage level and maintains constant the amount of a first current, and the second bias unit receives an external reference signal, responds to a control voltage, and controls the amount of a second current to be the same as the amount of the first current, and the comparison unit compares a voltage level of a first node with a voltage level of a second node, and controls a voltage level of the control voltage according to the comparison result, and the amplifier unit compares a voltage level of an external input signal with a voltage level of the external reference signal, amplifies and outputs a voltage difference between the two compared signals, responds to the control voltage, and controls the amount of a third current to be the same as the amount of the first current although the level of the external reference signal is varied, such that the amplifier circuit and a circuit for receiving data can maintain a constant output swing range and a stable delay time irrespective of variations in the voltage levels of the external input signal or the external reference signal.