A clock signal delay path unit includes a first delay cell including a first root signal line for delaying and transmitting a clock signal, a first repeater to transmit the clock signal transmitted through the first root signal line without signal attenuation, and a second root signal line for delaying and transmitting the clock signal output from the first repeater, a second delay cell including a first inverting circuit configured to invert the clock signal provided from the first delay cell to generate an inverted clock signal, and a third delay cell including a first branch signal line for delaying and transmitting the inverted clock signal provided from the second delay cell, a second repeater to transmit the inverted clock signal transmitted through the first branch signal line, and a second branch signal line for delaying and transmitting the inverted clock signal output from the second repeater.

A clock signal delay path unit includes a first delay cell including a first root signal line for delaying and transmitting a clock signal, a first repeater to transmit the clock signal transmitted through the first root signal line without signal attenuation, and a second root signal line for delaying and transmitting the clock signal output from the first repeater, a second delay cell including a first inverting circuit configured to invert the clock signal provided from the first delay cell to generate an inverted clock signal, and a third delay cell including a first branch signal line for delaying and transmitting the inverted clock signal provided from the second delay cell, a second repeater to transmit the inverted clock signal transmitted through the first branch signal line, and a second branch signal line for delaying and transmitting the inverted clock signal output from the second repeater.

Group delay determination in a communication circuit is disclosed. The communication circuit includes a power amplifier circuit that amplifies a radio frequency (RF) signal based on a modulated voltage and a power management integrated circuit (PMIC) that generates the modulated voltage. Herein, the PMIC includes a group delay determination circuit to determine a relative group delay between the modulated voltage and a modulated current, which is internal to the power amplifier circuit and unknown to the PMIC, solely based on signals known to the PMIC. The determined relative group delay can help to time align the modulated voltage with the modulated current at the power amplifier circuit to improve error vector magnitude (EVM) and/or adjacent channel leakage ratio (ACLR). Further, by determining the relative group delay based on known signals to the PMIC, it is possible to achieve good time alignment between the modulated voltage and the modulated current.

Group delay determination in a communication circuit is disclosed. The communication circuit includes a power amplifier circuit that amplifies a radio frequency (RF) signal based on a modulated voltage and a power management integrated circuit (PMIC) that generates the modulated voltage. Herein, the PMIC includes a group delay determination circuit to determine a relative group delay between the modulated voltage and a modulated current, which is internal to the power amplifier circuit and unknown to the PMIC, solely based on signals known to the PMIC. The determined relative group delay can help to time align the modulated voltage with the modulated current at the power amplifier circuit to improve error vector magnitude (EVM) and/or adjacent channel leakage ratio (ACLR). Further, by determining the relative group delay based on known signals to the PMIC, it is possible to achieve good time alignment between the modulated voltage and the modulated current.

A comparator circuit with dynamic biasing comprises a comparator, first dynamic biasing generator, first extra biasing device, second dynamic biasing generator, and second extra biasing device. The comparator includes a biasing circuit, input stage, active loads, and output terminal. The input stage has a first input terminal, second input terminal, first current path, and second current path. The comparator is configured to output an output signal at the output terminal according to the first input signal and second input signal. The first dynamic biasing generator is coupled between a first detection node and the first extra biasing device coupled to the biasing circuit. The second dynamic biasing generator is coupled between a second detection node and the second extra biasing device coupled to the biasing circuit. The first and second detection nodes are between the input stage and the active loads.

A comparator circuit with dynamic biasing comprises a comparator, first dynamic biasing generator, first extra biasing device, second dynamic biasing generator, and second extra biasing device. The comparator includes a biasing circuit, input stage, active loads, and output terminal. The input stage has a first input terminal, second input terminal, first current path, and second current path. The comparator is configured to output an output signal at the output terminal according to the first input signal and second input signal. The first dynamic biasing generator is coupled between a first detection node and the first extra biasing device coupled to the biasing circuit. The second dynamic biasing generator is coupled between a second detection node and the second extra biasing device coupled to the biasing circuit. The first and second detection nodes are between the input stage and the active loads.

Clock alignment circuitry may include phase detection circuitry and programmable delay circuitry to facilitate aligning a data signal with a particular state of a clock signal. For example, phase detection circuitry may be disposed at a location of interest to monitor the relative timing of the clock signal and the data signal. Based on the monitored states, the programmable delay circuitry may determine the delay to be applied to the data signal (e.g., prior to propagating through logic operations and transmission to the location of interest) such that the data signal later arrives at the location of interest at a suitable time. Effectively, a programmable delay is added to the delay encountered by the data signal during processing and transmission to the location of interest such that the total delay results in the data signal arriving at the location of interest while the clock signal is in the desired state.

Clock alignment circuitry may include phase detection circuitry and programmable delay circuitry to facilitate aligning a data signal with a particular state of a clock signal. For example, phase detection circuitry may be disposed at a location of interest to monitor the relative timing of the clock signal and the data signal. Based on the monitored states, the programmable delay circuitry may determine the delay to be applied to the data signal (e.g., prior to propagating through logic operations and transmission to the location of interest) such that the data signal later arrives at the location of interest at a suitable time. Effectively, a programmable delay is added to the delay encountered by the data signal during processing and transmission to the location of interest such that the total delay results in the data signal arriving at the location of interest while the clock signal is in the desired state.

Circuits and methods for generating a bypass pulse to an RF circuit that increases the response time of the circuit to mode changes. Embodiments include a pulse generation circuit that it is self-initiated and self-terminated, generating a bypass pulse as a function of voltages V1 and V2 along a signal path. Voltage V3, a scaled version of V1, is compared to a voltage V4 derived from V2 and a pulse is output while V3>V4. The pulse temporarily lowers the signal path impedance, reducing the RC time constant of the signal path and allowing fast charging of components coupled to the signal path. The pulse may be used with any other circuit that needs a faster settling time after a mode change but is slowed down by an RC time constant. Usage also extends to providing for rapid discharge of the signal path by adding additional logic components.

A pulse stretcher is disclosed comprising, a stretcher input (10) and a stretcher output (20); an asynchronous finite state machine; and a delay generator (40) having a delay input connected to the stretcher output, and a delay output connected to a second input of the FSM. The asynchronous FSM comprises: a first Muller C-element gate (250) having an output connected to the stretcher output, a second Muller C-element gate (260) having an output; and a combinatorial logic circuit (270) connected to the stretcher input, to first and second inputs of each of the first and second C-elements. The first and second Muller C-element gates are cross-coupled via the combinatorial logic, such that the respective outputs of the C-element gates are complementary and, in response to receiving the input pulse at the stretcher input, the output of the first Muller C-element gate provides a stretched version of the input pulse.