Apparatus and method having reduced flicker noise
View Patent ↗One embodiment described is an apparatus that includes an active device structured in a semiconductor body. The semiconductor body may include a gate terminal to receive a switched bias signal, and a bulk terminal to receive a forward body-bias signal. A first circuit portion may be coupled to the gate terminal to provide the switched bias signal, and a second circuit portion may be coupled to the bulk terminal to provide the forward body-bias signal.
1. An apparatus comprising:
an active device structured in a semiconductor body comprising:
a source region;
a drain region;
a body region including a channel region, the channel region located between the source region and the drain region;
a gate terminal to receive an alternating bias signal,
a bulk terminal coupled to the body region and configured to receive a forward body-bias signal,
a first circuit portion coupled to the gate terminal to provide the alternating bias signal; and
a second circuit portion coupled to the bulk terminal to provide the forward body-bias signal; and
wherein the alternating bias signal and the body-bias signal are configured to reduce flicker noise of the apparatus.
2. An apparatus according to claim 1 , wherein the duty cycle of the alternating bias signal has a duty cycle different from 50%.
3. The apparatus according to claim 1 , wherein the body-bias signal is a switched signal and the alternating bias signal and the body-bias signal are out of phase.
4. An apparatus according to claim 3 , wherein the alternating bias signal and the forward body-bias signal are phase-shifted to each other by 180°.
5. An apparatus according to claim 3 , wherein the alternating bias signal and the forward body-bias signal are asynchronous to each other.
6. An apparatus according to claim 3 , wherein the duty cycle of the forward body-bias signal has a duty cycle different from 50%.
7. The apparatus according to claim 3 , wherein the body-bias signal is derived from the bias signal.
8. Semiconductor circuitry for reduced flicker noise processing of a frequency signal, comprising:
a field effect transistor comprising:
a source region;
a drain region;
a body region including a channel region, the channel region located between the source region and the drain region;
a gate terminal to receive an alternating bias signal,
a bulk terminal coupled to the body region and configured to receive a forward body-bias signal,
a first circuit portion to provide the alternating bias signal,
a second circuit portion to provide the forward back-bias signal, the forward back-bias signal being a voltage between the bulk terminal and the source terminal; and
wherein the alternating bias signal and the body-bias signal are configured to reduce flicker noise of the apparatus.
9. A semiconductor circuitry according to claim 8 comprising:
a nonlinear circuit portion incorporating the field effect transistor.
10. A semiconductor circuitry according to claim 9 , wherein the nonlinear circuit portion comprises at least one of:
an oscillator circuitry, or
a mixer circuitry.
11. A semiconductor circuitry according to claim 8 , comprising:
a current source incorporating the field effect transistor.
12. A semiconductor circuitry according to claim 8 , wherein the forward back-bias signal provides an alternating bias.
13. The semiconductor circuitry according to claim 12 , wherein the forward back-bias signal is derived from the alternating bias signal, and the alternating bias signal being out of phase to the forward body-bias signal.
14. The semiconductor circuitry according to claim 8 , wherein the second circuit portion is disposed to provide the forward back-bias signal whenever the field effect transistor is in an off state in circuitry operation.
15. A method for operating an active device with less flicker noise, the method comprising:
supplying an alternating bias signal to a gate terminal of the active device;
supplying a forward body-bias signal to a bulk terminal of the active device, the bulk terminal coupled to a body region of the active device that includes a channel region of the active device; and
reducing flicker noise of the active device using the alternating bias signal and the forward body-bias signal.
16. A method according to claim 15 , wherein supplying the forward body-bias signal includes supplying an alternating forward body-bias signal.
17. A method according to claim 16 , wherein the alternating bias signal and the alternating forward body-bias signal are phase-shifted to each other by 180°.
18. A method according to claim 16 , wherein the alternating bias signal and the alternating forward body-bias signal are asynchronous to each other.
19. A method according to claim 15 , wherein the duty cycle of the alternating bias signal has a duty cycle different from 50%.
20. A method according to claim 16 , wherein the duty cycle of the alternating forward body-bias signal has a duty cycle different from 50%.
21. A method according to claim 15 , wherein the forward body-bias signal provides a constant bias.
22. The method according to claim 16 , wherein the supplying the alternating forward body-bias signal includes deriving the alternating forward body-bias signal from the alternating bias signal.
23. The semiconductor circuitry according to claim 15 , providing the forward back-bias signal to the bulk terminal whenever the active device is in an off state.