Application of control signal and forward body-bias signal to an active device
View Patent ↗The present disclosure relates to constructing and operating a transistor or other active device with significantly reduced flicker noise.
1. An active device comprising:
a gate terminal configured to receive a control signal having a first signal characteristic; and
a bulk terminal configured to receive a forward body-bias signal, the forward body-bias signal having a second signal characteristic, the first and second signal characteristics selected such that the forward body-bias signal cycles between an “on” state and an “off” state a plurality of times during a single cycle of the control signal and the forward body-bias signal is in the “on” state for at least a portion of time when the control signal is in an “off” state and the forward body-bias signal is in the “off” state for at least a portion of time when the control signal is in the “off” state and for at least a portion of time when the control signal is in an “on” state.
2. The active device of claim 1 , wherein the first signal characteristic is at least one of an amplitude, a duty cycle, a phase or fixed time shift, or an operating period characteristic, and wherein the second signal characteristic is at least one of an amplitude, a duty cycle, a phase or fixed time shift, or an operating period characteristic, and wherein at least one value of the first signal characteristic of the control signal differs from a respective value of the second signal characteristic of the forward body-bias signal.
3. The active device of claim 1 , wherein the first signal characteristic is a frequency and phase spectra characteristic and the second signal characteristic is a frequency and phase spectra characteristic, and wherein the first signal characteristic of the control signal differs in value from the second signal characteristic of the forward body-bias signal.
4. A method for operating an active device having a gate terminal and a bulk terminal, the method comprising:
applying a control signal to the gate terminal;
applying a forward body-bias signal to the bulk terminal;
wherein the control signal cycles between an “on” state and an “off” state a plurality of times during a single cycle of the forward body-bias signal such that the forward body-bias signal is in an “on” state for at least a portion of time when the control signal is in the “off” state and the forward body-bias signal is in an “off” state for at least a portion of time when the control signal is in the “off” state and for at least a portion of time when the control signal is in the “on” state.
5. A method according to claim 4 , wherein
the forward body-bias signal and the control signal are periodic signals, a frequency of the fundamental frequency of a harmonic series of the forward body-bias signal is different from a frequency of the fundamental frequency of a harmonic series of the control signal or
the frequency of the fundamental frequency of the harmonic series of the forward body-bias signal has approximately the same value as the frequency of the fundamental frequency of the harmonic series of the control signal and the fundamental frequency of the harmonic series of the forward body-bias signal has approximately the same value as the fundamental frequency of the harmonic series of the control signal.
6. A method according to claim 5 , wherein the frequency of the fundamental frequency of the harmonic series of the forward body-bias signal is greater than three times the frequency of the fundamental frequency of the harmonic series of the control signal.
7. A method according to claim 4 , further comprising applying a signal to be processed to the gate terminal, a source terminal, a drain terminal, or the bulk terminal, a frequency or phase spectra of at least one of the forward body-bias signal or the control signal is different than a frequency or phase spectra of the signal to be processed applied to the gate terminal, the source terminal, the drain terminal, or the bulk terminal.
8. A method according to claim 7 , wherein a lower frequency boundary of the frequency or phase spectra of the forward body-bias signal or the control signal is greater than three times a lower frequency boundary or phase spectra of the signal applied to the gate terminal or the source terminal or the drain terminal or the bulk terminal.
9. A method according to claim 7 , wherein a center frequency of the frequency or phase spectra of the forward body-bias signal or the control signal is separated from a center frequency of the frequency or phase spectra of the signal to be processed by a frequency bandwidth of the forward body-bias signal, the control signal, or the signal to be processed.
10. A method according to claim 9 , wherein the frequency or phase spectra of the forward body-bias signal has a first bandwidth, the frequency or phase spectra of the control signal has a second bandwidth, and the frequency or phase spectra of the signal to be processed has a third bandwidth, wherein the frequency or phase spectra of the signal to be processed is not overlapping with the frequency or phase spectra of the forward body-bias signal or the frequency or phase spectra of the control signal.
11. A method according to claim 4 , wherein a duty cycle of the forward body-bias signal is different than a duty cycle of the control signal.
12. A method according to claim 4 , further comprising applying a signal to be processed to the gate terminal or a source terminal or a drain terminal or the bulk terminal, wherein an amplitude, duty cycle, phase, or operating period of at least one of the forward body-bias signal or the control signal is different than an amplitude, duty cycle, phase, or operating period of the signal to be processed applied to the gate terminal or the source terminal or the drain terminal or the bulk terminal.
13. A method according to claim 4 , further comprising applying a signal to be processed, wherein a frequency or phase spectra of at least one of the forward body-bias signal or the control signal is different than a frequency or phase spectra of the signal to be processed.
14. A method according to claim 4 , wherein an amplitude and a duty cycle of the forward body-bias signal are selected to maximize in average a deviation of an occupation probability of traps from 50% occupation probability in one or more portions of the active device.
15. A method according to claim 4 , wherein an operating period or fixed time shift of a signal to be processed is different than an operating period or fixed time shift of the forward body-bias signal or the control signal.
16. A method according to claim 4 , wherein a frequency and phase spectra of the forward body-bias signal is different from a frequency and phase spectra of the control signal.
17. A method for operating an active device in a substrate, the active device having a source, a gate, a channel and a drain, the method comprising:
applying a control signal to the gate;
applying a forward body-bias signal to a bulk terminal;
wherein the forward body-bias signal cycles between an “on” state and an “off” state a plurality of times during a single cycle of the control signal, such that the forward body-bias signal establishes a gate to bulk voltage that drives the channel into a carrier accumulation condition for at least a portion of time when the control signal is at or below a threshold voltage for channel carrier inversion of the active device and the forward body-bias signal is placed in a condition that does not drive the channel into carrier accumulation for at least a portion of time when the control signal is above the threshold voltage for channel carrier inversion of the active device and for at least a portion of time when the control signal is at or below the threshold for channel carrier inversion of the active device.
18. A wireless communication device comprising an active device according to claim 1 .
19. The active device of claim 1 , wherein a frequency of the forward body-bias signal is higher than a frequency of the control signal, such that the forward body-bias signal cycles between the “on” state and the “off” state a plurality of times during a single cycle of the control signal and the forward body-bias signal is in the “on” state for at least a portion of time when the control signal is in the “off” state and the forward body-bias signal is in the “off” state for at least a portion of time when the control signal is in the “off” state and for at least a portion of time when the control signal is in the “on” state.
20. The method of claim 4 , wherein a period of the forward body-bias signal is higher than a period of the control signal, such that the control signal cycles between the “on” state and the “off” state a plurality of times during a single cycle of the forward body-bias signal and the forward body-bias signal is in the “on” state for at least a portion of time when the control signal is in the “off” state and the forward body-bias signal is in the “off” state for at least a portion of time when the control signal is in the “off” state and for at least a portion of time when the control signal is in the “on” state.