Abstract: A delayed lock loop for preventing a stuck fail in a dead-zone includes a clock buffering block for generating a first and a second internal clock signals; a phase comparison block for delaying a feedback signal by a first predetermined value and for respectively comparing a phase of a delayed feedback signal and a phase of the feedback signal with a phase of the external clock signal; a clock selecting block for selecting one of the first and second internal clock signals based on one comparison result to thereby generate a selected internal clock signal; a stuck checking block for determining a delay value based on the other comparison result; a delay line block for delaying the selected internal clock signal by the delay value; and an output buffer for buffering an outputted signal from the delay line block to thereby generating a DLL clock signal.

Abstract: A power-down mode exit control circuit enables a memory device to exit from an initially set power-down mode state using a clock enable signal. Specifically, although a clock enable signal is inputted in an unstable state at an initial operation indicating that a supply of a supply voltage is started, the present invention provides the power-down mode exit control circuit which is capable of escaping from the power-down mode at an internally set correct time. For this, the present invention comprises: a clock enable signal sensor for sensing an activation or deactivation state of a clock enable signal; and a power-down mode exit signal generator for activating and outputting a power-down mode exit signal in accordance with the activation state of the clock enable signal sensed by the sensor, after storing information related to the deactivation state of the clock enable signal sensed by the sensor.

Abstract: A delayed lock loop for preventing a stuck fail in a dead-zone includes a clock buffering block for generating a first and a second internal clock signals; a phase comparison block for delaying a feedback signal by a first predetermined value and for respectively comparing a phase of a delayed feedback signal and a phase of the feedback signal with a phase of the external clock signal; a clock selecting block for selecting one of the first and second internal clock signals based on one comparison result to thereby generate a selected internal clock signal; a stuck checking block for determining a delay value based on the other comparison result; a delay line block for delaying the selected internal clock signal by the delay value; and an output buffer for buffering an outputted signal from the delay line block to thereby generating a DLL clock signal.

Abstract: An apparatus for adjusting a clock signal, including: a clock multiplexing unit for receiving an external clock signal, an external clock bar signal and a feed-backed clock signal in order to select one of the external clock signal and the external clock bar signal as an output signal of the clock multiplexing unit based on a result of comparing a phase of the external clock signal with a phase of the feed-backed clock signal; and a delay locked loop (DLL) for generating a duty corrected clock signal and the feed-backed clock signal in response to the output signal of the clock multiplexing unit.

Abstract: A delayed lock loop for preventing a stuck fail in a dead-zone includes a clock buffering block for generating a first and a second internal clock signals; a phase comparison block for delaying a feedback signal by a first predetermined value and for respectively comparing a phase of a delayed feedback signal and a phase of the feedback signal with a phase of the external clock signal; a clock selecting block for selecting one of the first and second internal clock signals based on one comparison result to thereby generate a selected internal clock signal; a stuck checking block for determining a delay value based on the other comparison result; a delay line block for delaying the selected internal clock signal by the delay value; and an output buffer for buffering an outputted signal from the delay line block to thereby generating a DLL clock signal.

Abstract: A semiconductor device for correcting a duty of a clock signal includes a first clock buffer for receiving an external clock signal through a non-inverting terminal of the first clock buffer and for receiving an external clock bar signal through an inverting terminal of the first clock buffer to thereby output a first clock input signal; a second clock buffer for receiving the external clock bar signal through the non-inverting terminal of the first clock buffer and for receiving the external clock signal through the inverting terminal of the first clock buffer to thereby output a second clock input signal; and a delay locked loop (DLL) for receiving the first clock input signal and the second clock input signal to thereby generate a duty corrected clock signal.

Abstract: A refresh control circuit for use in a semiconductor memory device having a plurality of banks, including: a bank number signal generator for generating a plurality of bank number signals having a predetermined delay time between generation timings of the plurality of bank number signals based on a refresh signal and a reference signal; and a bank selection unit for generating a plurality of bank selection signals in response to the plurality of bank number signals and a piled-refresh control signals to thereby refresh the plurality of banks.

Abstract: An apparatus for adjusting a clock signal, including: a clock multiplexing unit for receiving an external clock signal, an external clock bar signal and a feed-backed clock signal in order to select one of the external clock signal and the external clock bar signal as an output signal of the clock multiplexing unit based on a result of comparing a phase of the external clock signal with a phase of the feed-backed clock signal; and a delay locked loop (DLL) for generating a duty corrected clock signal and the feed-backed clock signal in response to the output signal of the clock multiplexing unit.

Abstract: A refresh control circuit for use in a semiconductor memory device having a plurality of banks, including: a bank number signal generator for generating a plurality of bank number signals having a predetermined delay time between generation timings of the plurality of bank number signals based on a refresh signal and a reference signal; and a bank selection unit for generating a plurality of bank selection signals in response to the plurality of bank number signals and a piled-refresh control signals to thereby refresh the plurality of banks.

Abstract: A power-down mode exit control circuit enables a memory device to exit from an initially set power-down mode state using a clock enable signal. Specifically, although a clock enable signal is inputted in an unstable state at an initial operation indicating that a supply of a supply voltage is started, the present invention provides the power-down mode exit control circuit which is capable of escaping from the power-down mode at an internally set correct time. For this, the present invention comprises: a clock enable signal sensor for sensing an activation or deactivation state of a clock enable signal; and a power-down mode exit signal generator for activating and outputting a power-down mode exit signal in accordance with the activation state of the clock enable signal sensed by the sensor, after storing information related to the deactivation state of the clock enable signal sensed by the sensor.

Abstract: An apparatus for adjusting a clock signal, including: a clock multiplexing unit for receiving an external clock signal, an external clock bar signal and a feed-backed clock signal in order to select one of the external clock signal and the external clock bar signal as an output signal of the clock multiplexing unit based on a result of comparing a phase of the external clock signal with a phase of the feed-backed clock signal; and a delay locked loop (DLL) for generating a duty corrected clock signal and the feed-backed clock signal in response to the output signal of the clock multiplexing unit.

Abstract: A refresh control circuit for use in a semiconductor memory device having a plurality of banks, including: a bank number signal generator for generating a plurality of bank number signals having a predetermined delay time between generation timings of the plurality of bank number signals based on a refresh signal and a reference signal; and a bank selection unit for generating a plurality of bank selection signals in response to the plurality of bank number signals and a piled-refresh control signals to thereby refresh the plurality of banks.

Abstract: Disclosed is a semiconductor memory device capable of reducing chip area by precharging all banks simultaneously. The semiconductor memory device includes: a command decoder for generating an auto refresh signal in response to an external command; an active information signal generator for generating an active information signal in response to a bank grouping signal when the auto refresh signal is activated; a tRAS controller for generating a tRAS control signal for each bank in response to an activated bank active detection signal, wherein the tRAS control signal maintains an active state during a row active time; a precharge information signal generator for generating a precharge information signal in response to the tRAS control signal of a last activated bank; and a bank control signal generator for generating a bank active signal in response to the active information signal and generates a bank precharge signal in response to the precharge information signal, respectively.

Abstract: A delay locked loop (DLL) capable of correcting a duty ratio including: a clock buffer for receiving an external clock signal and an inverted external clock signal to generate a rising edge clock signal; a delay unit for delaying the rising edge clock signal based on a first comparison signal in order to generate a first internal clock signal, a second internal clock signal, a first delay locking signal and a second delay locking signal; a duty correction unit for receiving the first and the second internal clock signals and the first and the second delay locking signals to generate a mixed clock signal; a delay model unit for delaying the mixed clock signal to generate a feed-backed clock signal; and a first phase detector for receiving the external clock signal and the feed-backed clock signal to generate the first comparison signal.

Abstract: A power-down mode exit control circuit enables a memory device to exit from an initially set power-down mode state using a clock enable signal. Specifically, although a clock enable signal is inputted in an unstable state at an initial operation indicating that a supply of a supply voltage is started, the present invention provides the power-down mode exit control circuit which is capable of escaping from the power-down mode at an internally set correct time. For this, the present invention comprises: a clock enable signal sensor for sensing an activation or deactivation state of a clock enable signal; and a power-down mode exit signal generator for activating and outputting a power-down mode exit signal in accordance with the activation state of the clock enable signal sensed by the sensor, after storing information related to the deactivation state of the clock enable signal sensed by the sensor.

Abstract: An apparatus for detecting locking information of a DLL clock in a semiconductor memory device includes a delayed locked loop for generating a first comparison signal and a first delay end signal; a phase state storing block for receiving the first comparison signal and the first delay end signal to thereby generate a locking selection signal; and a locking information detector for generating a locking state signal presenting the locking information in response to the first comparison signal, the first delay end signal and the locking selection signal.

Abstract: A register controlled delay locked loop (DLL), including: a coarse delay line for generating a delayed input clock signal by delaying an external clock signal; a fine delay line unit for receiving the delayed input clock signal in order to generate a first fine delayed clock signal and a second fine delayed clock signal; a phase detector for comparing phases of the external clock signal and a feed-backed clock signal in order to generate a phase detection signal based on the comparison result; a phase mixer for generating a mixed clock signal by mixing phases of the first fine delayed clock signal and the second fine delayed clock signal based on a weight value; and a mixer controller for generating the weight value based on the phase detection signal.

Abstract: Disclosed is a semiconductor memory device capable of reducing chip area by precharging all banks simultaneously. The semiconductor memory device includes: a command decoder for generating an auto refresh signal in response to an external command; an active information signal generator for generating an active information signal in response to a bank grouping signal when the auto refresh signal is activated; a tRAS controller for generating a tRAS control signal for each bank in response to an activated bank active detection signal, wherein the tRAS control signal maintains an active state during a row active time; a precharge information signal generator for generating a precharge information signal in response to the tRAS control signal of a last activated bank; and a bank control signal generator for generating a bank active signal in response to the active information signal and generates a bank precharge signal in response to the precharge information signal, respectively.

Abstract: A digital DLL apparatus and a method for correcting a duty cycle are disclosed. The apparatus includes: a delay line unit for receiving external clock signal and generating first and second delayed internal clock signals by delaying the external clock signal; a duty error controller for receiving the first and second delayed clock signals and outputting a first duty controlled clock signal and second duty controlled clock signal by shifting edges of the first and second delayed internal clock signals; and a delay model unit for compensating a delay of the duty controlled clock signal by estimating a delay amount of system. The present invention can correct the duty error by using the phase mixer and generate an internal clock signal having 50% of duty cycle.

Abstract: A register controlled delay locked loop (DLL), including: a coarse delay line for generating a delayed input clock signal by delaying an external clock signal; a fine delay line unit for receiving the delayed input clock signal in order to generate a first fine delayed clock signal and a second fine delayed clock signal; a phase detector for comparing phases of the external clock signal and a feed-backed clock signal in order to generate a phase detection signal based on the comparison result; a phase mixer for generating a mixed clock signal by mixing phases of the first fine delayed clock signal and the second fine delayed clock signal based on a weight value; and a mixer controller for generating the weight value based on the phase detection signal.