摘要:
A charge pumping circuit includes a first switch for controlling one of push and pull operations in accordance with a first control signal; a current mirror circuit constructed from transistors each having a different polarity from the first switch; a second switch for controlling current input to the current mirror circuit in accordance with a second control signal, the second switch being constructed from a transistor having the same characteristic as a transistor used for constructing the first switch; a first MOS capacitor one end of which is connected to an input side of the current mirror circuit; a second MOS capacitor receiving, at one end thereof, a current concerned with the push and pull operations; and a voltage buffer connected to the first and second MOS capacitors. The other of the push and pull operations is performed with an output current of the current mirror circuit.
摘要:
A time required for an output voltage of a source follower to rise from Low to a predetermined voltage depends on a bias voltage. Therefore, by setting a converged voltage of an output voltage to be high by increasing the bias voltage, the time required to rise up to the predetermined voltage can be reduced. Therefore, a first source follower which is biased so that the converged value of the output voltage becomes a predetermined Hi voltage when an input data signal goes from Low to Hi, and a second source follower which is biased so as to become the Hi voltage after a period of one clock when an input data signal goes from Low to Hi, are used. The two source followers are operated with appropriate timing.
摘要:
A delay element generates a delayed clock signal which transitions with a delay from a rising (or falling) of a reference clock signal by a delay amount determined based on an output of a loop filter. A signal generation circuit generates two signals which complementarily change according to rising and falling of the reference clock signal and a transition of the delayed clock signal. A charge pump circuit performs on the loop filter, according to these two signals, a push (or pull) operation during an interval extending from a rising (or falling) of the reference clock signal to the transition of the delayed clock signal and a pull (or push) operation during an interval extending from the transition of the delayed clock signal to a falling (or rising) of the reference clock signal.
摘要:
A selection section (105) selects a step voltage, among a plurality of step voltages (SV1, SV2, SV3, . . . ) each having a voltage value changing stepwise, corresponding to the digital value of digital data (D-DATA). For each of the plurality of step voltages (SV1, SV2, SV3, . . . ), different digital values are allocated to different steps of the step voltage. An amplifier section (106) amplifies the step voltage selected by the selection section (105). An output section (107) outputs the step voltage amplified by the amplifier section (106) as an output voltage (Vout) for a time period corresponding to the digital value of the digital data (D-DATA).
摘要:
A delay element generates a delayed clock signal which transitions with a delay from a rising (or falling) of a reference clock signal by a delay amount determined based on an output of a loop filter. A signal generation circuit generates two signals which complementarily change according to rising and falling of the reference clock signal and a transition of the delayed clock signal. A charge pump circuit performs on the loop filter, according to these two signals, a push (or pull) operation during an interval extending from a rising (or falling) of the reference clock signal to the transition of the delayed clock signal and a pull (or push) operation during an interval extending from the transition of the delayed clock signal to a falling (or rising) of the reference clock signal.
摘要:
A phase adjustment circuit includes first to nth two-phase adjustment circuits. Each two-phase adjustment circuit includes a first logic circuit for performing logical sum of two input signals, a second logic circuit for performing logical product of the two input signals, a first delay circuit having a signal delay equal to that of the second logic circuit and configured to delay a signal output from the first logic circuit, and a second delay circuit having a signal delay equal to that of the first logic circuit and configured to delay a signal output from the second logic circuit. Two signals output from two of the two-phase adjustment circuits in a certain stage are input into one of the two-phase adjustment circuits in the next stage.
摘要:
A selection section (105) selects a step voltage, among a plurality of step voltages (SV1, SV2, SV3, . . . ) each having a voltage value changing stepwise, corresponding to the digital value of digital data (D-DATA). For each of the plurality of step voltages (SV1, SV2, SV3, . . . ), different digital values are allocated to different steps of the step voltage. An amplifier section (106) amplifies the step voltage selected by the selection section (105). An output section (107) outputs the step voltage amplified by the amplifier section (106) as an output voltage (Vout) for a time period corresponding to the digital value of the digital data (D-DATA).
摘要:
A charge pumping circuit includes a first switch for controlling one of push and pull operations in accordance with a first control signal; a current mirror circuit constructed from transistors each having a different polarity from the first switch; a second switch for controlling current input to the current mirror circuit in accordance with a second control signal, the second switch being constructed from a transistor having the same characteristic as a transistor used for constructing the first switch; a first MOS capacitor one end of which is connected to an input side of the current mirror circuit; a second MOS capacitor receiving, at one end thereof, a current concerned with the push and pull operations; and a voltage buffer connected to the first and second MOS capacitors. The other of the push and pull operations is performed with an output current of the current mirror circuit.
摘要:
An oscillator circuit increases and reduces signal levels of first and second oscillation signals in a complementary manner in response to a transition of a signal level of a reference clock. An oscillation control circuit compares each of the signal levels of the first and second oscillation signals to a comparison voltage, and causes the signal level of the reference clock to transition according to results of the comparison. A reference control circuit increases or reduces the comparison voltage so that a difference between a signal level of an intermediate signal which is proportional to respective swings of the first and second oscillation signals and a reference voltage is reduced.
摘要:
The charge pump circuit includes: a first switch for controlling either one of push operation and pull operation based on a first control signal; a current mirror circuit composed of a transistor different in attribute from the first switch; and a second switch composed of a transistor same in characteristic as a transistor constituting the first switch, for controlling input of a current into the current mirror circuit based on a second control. The other operation, the push operation or the pull operation, is performed with a current output from the current mirror circuit.