Method and apparatus for reducing oscillator pull in a CMOS wireless transceiver integrated circuit

A monolithic integrated circuit comprising:

• a substrate;
• a first set of one or more subcircuits on the substrate;
• a second set of one or mare subcircuits on the substrate;
• and
• a bias current supply coupled to the first and second sets to provide bias current to the first and second sets, and including:
• a first bias circuit on the substrate coupled to and to supply bias current to a first subcircuit of the first set, the first bias circuit including a first current modulator having a first switch input to control the rate of change of supplied bias current in response to the first switch input, the first switch input to indicate that the bras current is to start or stop being supplied to the first subcircuit, wherein the first current modulator is a ramp generator such that the bias current supplied to the first subcircuit approximates a ramp function in time following the first switch input indicating that the bias current is to start or stop being supplied to the first subcircuit.

A monolithic integrated circuit comprising:

• a substrate;
• a first set of one or more subcircuits on the substrate;
• a second set of one or mare subcircuits on the substrate;
• and
• a bias current supply coupled to the first and second sets to provide bias current to the first and second sets, and including:
• a first bias circuit on the substrate coupled to and to supply bias current to a first subcircuit of the first set, the first bias circuit including a first current modulator having a first switch input to control the rate of change of supplied bias current in response to the first switch input the first switch input to indicate that the bras current is to start or stop being supplied to the first subcircuit, wherein the second bias circuit includes a second current modulator having a second switch input to control the rate of change of supplied bias current in response to the second switch input, the second switch input to indicate that the bias current is to start being supplied to the second subcircuit,
• wherein the first and second subcircuits operate at mutually exclusive time periods.

In a monolithic integrated circuit, a method of providing bias current comprising:

• partitioning at least part of the integrated circuit into a first set of one or more sub-circuits and a second set of one or more sub-circuits, such that the first set and second set operate in mutually exclusive time periods;
• providing bias current to the first set of subcircuits, including switchably providing bias current to one or more subcircuits of the first set only for period of operation of the first set of subcircuits;
• and
• providing bias current to the second set of subcircuits,
• the switchably providing including controlling the rate of change of supplied bias current during the switching on or off of bias current.

A monolithic integrated circuit comprising:

• an oscillator operating at a nominal frequency;
• a first set of one or more subcircuits;
• a second set of one or more subcircuits, the first and second sets to operate during mutually exclusive time periods;
• and
• a power supply coupled to, and to supply power to, the first and second sets and to the oscillator, the power supply including
• a first bias circuit coupled to and to supply bias current to a first subcircuit of the first set, the first bias circuit including a first current modulator having a first switch input to control the rate of change of supplied bias current in response to the first switch input, the first switch input to indicate that the bias current is to start or stop being supplied to the first subcircuit,
• the control of the rate of change to limit perturbations to the frequency of the oscillator during switching on and off of the first subcircuit.

A monolithic radio frequency (RF) integrated circuit comprising:

• a substrate;
• a first set of one or more RF subcircuits on the substrate;
• a second set of one or more RF subcircuits on the substrate;
• and
• a bias current supply coupled to the first and second sets to provide bias current to the first and second sets, and including:
• a first bias circuit on the substrate coupled to and to supply bias current to a first RF subcircuit of the first set, the first bias circuit including a first current modulator having a first switch input to control the rate of chance of supplied bias current in response to the first switch input, the first switch input to indicate that the bias current is to start or stop being supplied to the first RF subcircuit,
• wherein the integrated circuit is for operation as a radio transceiver including a receiver and a transmitter,
• wherein the transmitter includes the first set of RF subcircuits and the receiver includes the second set of RF subcircuits, and
• wherein the first RF subcircuit includes an RF power amplifier in the transmitter.

A monolithic radio frequency (RF) integrated circuit comprising:

• a substrate;
• a first set of one or more RF subcircuits on the substrate;
• a second set of one or more RF subcircuits on the substrate;
• and
• a bias current supply coupled to the first and second sets to provide bias current to the first and second sets, and including:
• a first bias circuit on the substrate coupled to and to supply bias current to a first RF subcircuit of the first set, the first bias circuit including a first current modulator having a first switch input to control the rate of change of supplied bias current in response to the first switch input the first switch input to indicate that the bias current is to start or stop being supplied to the first RF subcircuit, wherein the first current modulator is a ramp generator such that the bias current supplied to the first RF subcircuit approximates a ramp function in time following the first switch input indicating that the bias current is to start or stop being supplied to the first RF subcircuit.

A monolithic radio frequency (RF) integrated circuit comprising:

• a substrate;
• a first set of one or more RF subcircuits on the substrate;
• a second set of one or more RF subcircuits on the substrate;
• and
• a bias current supply coupled to the first and second sets to provide bias current to the first and second sets, and including:
• a first bias circuit on the substrate coupled to and to supply bias current to a first RF subcircuit of the first set, the first bias circuit including a first current modulator having a first switch input to control the rate of change of supplied bias current in response to the first switch input the first switch input to indicate that the bias current is to start or stop being supplied to the first RF subcircuit, wherein the second bias circuit includes a second current modulator having a second switch input to control the rate of change of supplied bias current in response to the second switch input, the second switch input to indicate that the bias current is to start being supplied to the second RF subcircuit,
• wherein the first and second RF subcircuits operate at mutually exclusive time periods.

In a monolithic radio frequency (RF) integrated circuit, a method of providing bias current comprising:

• partitioning at least part of the integrated circuit into a first set of one or more RF subcircuits and a second set of one or more RF subcircuits, such that the first set and second set operate in mutually exclusive time periods;
• providing bias current to the first set of RF subcircuits, including switchably providing bias current to one or more RF subcircuits of the first set only for period of operation of the first set of RF subcircuits;
• and
• providing bias current to the second set of RF subcircuits, the switchably providing including controlling the rate of change of supplied bias current during the switching on or off of bias current,
• wherein the integrated circuit includes an oscillator operating at a nominal frequency, and wherein controlling the rate of change of supplied bias current during the switching on or off of bias current is to limit perturbations to the oscillator nominal frequency.

A monolithic radio frequency (RF) integrated circuit comprising:

• an oscillator operating at a nominal frequency;
• a first set of one or more RF subcircuits;
• a second set of one or more RF subcircuits, the first and second sets to operate during mutually exclusive time periods;
• and
• a power supply coupled to, and to supply power to, the first and second sets and to the oscillator, the power supply including
• a first bias circuit coupled to and to supply bias current to a first RF subcircuit of the first set, the first bias circuit including a first current modulator having a first switch input to control the rate of change of supplied bias current in response to the first switch input, the first switch input to indicate that the bias current is to start or stop being supplied to the first RF subcircuit,
• the control of the rate of change to limit perturbations to the frequency of the oscillator during switching on and off of the first RF subcircuit.