Delay line, a delay locked loop circuit and a semiconductor apparatus using the delay line and the delay locked loop circuit
A delay locked loop circuit includes a delay line, a phase detector, a selection controller, and a charge pump. The delay line delays, based on a delay control voltage, a reference clock signal to generate an internal clock signal and a feedback clock signal. The phase detector compares phases of the internal clock signal and the feedback clock signal to generate a first detection signal and a second detection signal. The selection controller provides the reference clock signal as an up-signal and a down-signal. The charge pump generates the delay control voltage based on the up-signal and the down-signal.
1. A delay locked loop circuit comprising:
a frequency detector configured to detect a frequency of a reference clock signal to generate a frequency detection signal;
a delay line configured to delay, based on a delay control voltage, the reference clock signal to generate an internal clock signal and a feedback clock signal;
a phase detector configured to compare phases of the internal clock signal and the feedback clock signal to generate a first detection signal and a second detection signal;
a selection controller configured to provide the first detection signal and the second detection signal respectively as an up-signal and a down-signal when the frequency detection signal is disabled, and to provide the reference clock signal as the up-signal and the down-signal when the frequency detection signal is enabled; and
a charge pump configured to generate the delay control voltage based on the up-signal and the down-signal.
2. The delay locked loop circuit of claim 1 ,
wherein the frequency detector enables the frequency detection signal when the frequency of the reference clock signal is less than a reference frequency, and
wherein the frequency detector disables the frequency detection signal when the frequency of the reference clock signal is greater than the reference frequency.
3. The delay locked loop circuit of claim 1 ,
wherein the charge pump includes:
a pull-up circuit configured to provide an output node with an up-current based on the up-signal;
a pull-down circuit configured couple the output node to a down-current, based on the down-signal, to discharge the output node; and
a turn-on control circuit configured to provide the output node with an additional up-current based on the frequency detection signal, and
wherein the delay control voltage is output from the output node.
4. The delay locked loop circuit of claim 3 ,
wherein an amount of the up-current is substantially the same as an amount of the down-current, and an amount of the additional up-current is less than the amount of the up-current or the amount of the down-current.
5. The delay locked loop circuit of claim 3 ,
wherein the delay line includes at least one delay cell configured to delay, based on the delay control voltage, an input signal to generate an output signal, and
wherein the at least one delay cell is turned on based on the delay control voltage having a voltage level corresponding to a high logic level.
6. The delay locked loop circuit of claim 1 ,
wherein the charge pump includes:
a pull-up circuit configured to provide an output node with an up-current based on the up-signal;
a pull-down circuit configured to couple the output node to a down-current, based on the down-signal, to discharge the output node; and
a turn-on control circuit configured to discharge an additional down-current from the output node based on the frequency detection signal, and
wherein the delay control voltage is output from the output node.
7. The delay locked loop circuit of claim 5 ,
wherein an amount of the up-current is substantially the same as an amount of the down-current, and an amount of the additional down-current is less than the amount of the up-current or the amount of the down-current.
8. The delay locked loop circuit of claim 6 ,
wherein the delay line includes at least one delay cell configured to delay, based on the delay control voltage, an input signal to generate an output signal, and
wherein the at least one delay cell is turned on based on the delay control voltage having a voltage level corresponding to a low logic level.
9. A delay locked loop circuit comprising:
a delay line configured to delay, based on a delay control voltage, a reference clock signal to generate an internal clock signal and a feedback clock signal;
a phase detector configured to compare phases of the internal clock signal and the feedback clock signal to generate a first detection signal and a second detection signal;
a selection controller configured to provide the first detection signal and the second detection signal respectively as an up-signal and a down-signal when a deterioration enable signal is disabled, and to provide the reference clock signal as the up-signal and the down-signal when the deterioration enable signal is enabled; and
a charge pump configured to generate the delay control voltage based on the up-signal and the down-signal.