Abstract:
An oscillator includes at least one oscillator transistor having collector, emitter and base leads, a controllable current source connected between the emitter lead of the at least one oscillator transistor and a supply potential, and a frequency-determining element, such as an oscillating circuit, connected at least to the base or collector lead of the at least one oscillator transistor. A method for controlling the amplitude of the output signal of the oscillator includes supplying a direct voltage variation at the emitter lead of the at least one oscillator transistor resulting from a change in amplitude of a signal applied to the base lead of the at least one oscillator transistor as a controlled variable for the current of the controllable current source. The oscillator may also include a control amplifier. The emitter lead of the at least one oscillator transistor is connected to one input of the control amplifier and the other input of the control amplifier is connected to a reference potential. The reference potential is in a fixed relationship with a direct signal component of a signal present at the base lead of the at least one oscillator transistor. The current of the controllable current source is adjusted as a function of an output variable at the control amplifier.
Abstract:
A reference oscillator arrangement is provided for a communication apparatus capable of communicating according to a plurality of transport formats. The reference oscillator arrangement comprises a reference oscillator controller; a resonator core comprising a reference resonator and a driving circuit for the reference resonator, wherein the resonator core is arranged to provide an oscillating signal at a frequency of the reference resonator; and a reference oscillator buffer arrangement, connected to the resonator core, comprising an active circuit arranged to provide a reference oscillator output based on the oscillating signal. The reference oscillator controller is arranged to receive information about an applied transport format and control the driving circuit and/or the active circuit based on the information about the applied transport format. An oscillator arrangement, a communication device, methods therefor and a computer program are also disclosed.
Abstract:
An oscillator includes an input terminal, an oscillation circuit section configured to cause a resonator to resonate to output an oscillator signal, a digital input section to which a signal for controlling an oscillation frequency of the oscillation circuit section is input via the input terminal, and a first bias circuit section including a constant current source configured to supply a reference current to the digital input section.
Abstract:
Technologies are generally described for quadrature-based injection-locking of ring oscillators. In some examples, an external signal may be injected into a ring oscillator. Phase signals may be measured from within the ring oscillator and used to determine a mean quadrature error (MQE) that characterizes the difference in frequency between the external signal and the ring oscillator's natural frequency. A control signal may then be generated from the MQE and used to adjust the ring oscillator natural frequency to reduce the difference between the ring oscillator natural frequency and the external signal.
Abstract:
An oscillator includes an input terminal, an oscillation circuit section configured to cause a resonator to resonate to output an oscillator signal, a digital input section to which a signal for controlling an oscillation frequency of the oscillation circuit section is input via the input terminal, and a first bias circuit section including a constant current source configured to supply a reference current to the digital input section.
Abstract:
An oscillation circuit includes a temperature compensating section to which electric power is supplied from a main power supply and a backup power supply, an oscillating section, a function of which is compensated by a signal from the temperature compensating section, and a switch and a power-supply monitoring circuit configured to select, when the temperature compensating section is not operating, at least one of the main power supply and the backup power supply and control connection to the temperature compensating section.
Abstract:
According to one embodiment, a phase locked loop (PLL) circuit includes an application unit, a correlator, an integrator and a power supply noise canceller. The application unit applies the test signal to a power supply voltage. The correlator extracts a frequency error signal as a monitor signal and calculates a correlation value for the test signal and the monitor signal to generate a correlation signal. The integrator integrates the correlation signal to generate an integral signal. The power supply noise canceller provides a cancellation gain corresponding to the integral signal to the power supply voltage to which the test signal is applied, to generate a control signal.
Abstract:
High-speed CMOS ring voltage controlled oscillators with low supply sensitivity have been disclosed. According to one embodiment, a CML ring oscillator comprises a CML negative impedance compensation circuit comprising two cross coupled transistors and a resistor connected to the two transistors for resistive biasing and a CML interpolating delay cell connected in parallel with the CML negative impedance compensation. An impedance change of the CML negative impedance compensation due to supply variation counteracts an impedance change of the CML interpolating delay cell.
Abstract:
Voltage-controlled oscillation (100) is described. In an apparatus therefor, an inductor (120) has a tap and has or is coupled to a positive-side output node (105) and a negative side output node (106). The tap is coupled to receive a first current. A coarse grain capacitor array (130) is coupled to the positive-side output node (105) and the negative side output node (106) and is coupled to respectively receive select signals (168). A varactor (140) is coupled to the positive-side output node (105) and the negative side output node (106) and is coupled to receive a control voltage (143). The varactor (140) includes MuGFETs (141, 142). A transconductance cell (150) is coupled to the positive- side output node (105) and the negative side output node (106), and the transconductance cell (150) has a common node (107). A frequency scaled resistor network (160) is coupled to the common node (107) and is coupled to receive the select signals (168) for a resistance for a path for a second current.
Abstract:
A reference oscillator arrangement is provided for a communication apparatus capable of communicating according to a plurality of transport formats. The reference oscillator arrangement comprises a reference oscillator controller; a resonator core comprising a reference resonator and a driving circuit for the reference resonator, wherein the resonator core is arranged to provide an oscillating signal at a frequency of the reference resonator; and a reference oscillator buffer arrangement, connected to the resonator core, comprising an active circuit arranged to provide a reference oscillator output based on the oscillating signal. The reference oscillator controller is arranged to receive information about an applied transport format and control the driving circuit and/or the active circuit based on the information about the applied transport format. An oscillator arrangement, a communication device, methods therefor and a computer program are also disclosed.