Compact bypass and decoupling structure for millimeter-wave circuits
The disclosure generally relates to a compact bypass and decoupling structure that can be used in a millimeter-wave radio frequency integrated circuit (RFIC). For example, according to various aspects, an RFIC incorporating the compact bypass and decoupling structure may comprise a grounded substrate, a mid-metal ground plane, a bypass capacitor disposed between the grounded substrate and the mid-metal ground plane, and a decoupling inductor disposed over the mid-metal ground plane. The bypass capacitor may close a current loop in the RFIC and the decoupling inductor may provide damping in a supply network associated with the RFIC. Furthermore, the decoupling conductor may have a self-resonance substantially close to an operating band associated with the RFIC to increase series isolation, introduce substrate losses that facilitate the damping in the supply network, and prevent high-Q resonances.
1. An integrated circuit, comprising:
a shared supply node; and
a plurality of gain stages, wherein the plurality of gain stages each comprise:
gain stage circuitry disposed in a signal path;
a decoupling inductor having a first terminal connected to the shared supply node and a second terminal connected to the gain stage circuitry; and
a bypass capacitor having a first terminal connected to ground and a second terminal connected to the gain stage circuitry and to the second terminal of the decoupling inductor.
2. The integrated circuit recited in claim 1 , wherein the decoupling inductor and the bypass capacitor form a passive filtering network configured to isolate the gain stage circuitry from a current flowing on a supply line coupling the plurality of gain stages to the shared supply node.
3. The integrated circuit recited in claim 2 , wherein the isolated current flows from a last one of the plurality of gain stages.
4. The integrated circuit recited in claim 1 , wherein the decoupling inductor has a self-resonance substantially close to an operating band associated with the integrated circuit to increase series isolation in the integrated circuit, to introduce substrate losses that facilitate damping in a supply network that couples the plurality of gain stages according to a star intersection, and to prevent high-Q resonances.
5. The integrated circuit recited in claim 1 , wherein the bypass capacitor comprises one or more active elements, including at least one of a transistor or an accumulation mode capacitor.
6. The integrated circuit recited in claim 1 , incorporated into a transceiver configured to transmit and receive millimeter-wave wireless signals.
7. The integrated circuit recited in claim 6 , wherein the transceiver comprises an 802.11ad transceiver configured to transmit and receive the millimeter-wave wireless signals in a 60 GHz frequency band.
8. The integrated circuit recited in claim 6 , wherein the transceiver comprises a cellular transceiver configured to transmit and receive the millimeter-wave wireless signals in one or more of a 28 GHz frequency band or a 39 GHz frequency band.
9. The integrated circuit recited in claim 1 , incorporated into a wireless device configured to transmit and receive millimeter-wave wireless signals.
10. A method for stabilizing a supply network, comprising:
providing a shared supply node;
providing a signal path comprising a plurality of gain stages; and
providing a passive filtering network in each of the plurality of gain stages, wherein the passive filtering network comprises an inductor having a first terminal connected to the shared supply node and a second terminal connected to circuitry disposed in the signal path and a capacitor having a first terminal connected to ground and a second terminal connected to the circuitry disposed in the signal path and to the second terminal of the inductor.
11. The method recited in claim 10 , wherein the inductor and the capacitor are configured to isolate the circuitry disposed in the signal path from a current flowing on a supply line coupling the plurality of gain stages to the shared supply node.
12. The method recited in claim 11 , wherein the isolated current flows from a last one of the plurality of gain stages.
13. The method recited in claim 10 , wherein the inductor has a self-resonance substantially close to an operating band associated with the circuitry disposed in the signal path.
14. The method recited in claim 10 , wherein the capacitor comprises one or more active elements, including at least one of a transistor or an accumulation mode capacitor.
15. The method recited in claim 10 , wherein the shared supply node, the signal path, and the bypass and decoupling structure are provided in a transceiver configured to transmit and receive millimeter-wave wireless signals.
16. The method recited in claim 15 , wherein the transceiver comprises an 802.11ad transceiver configured to transmit and receive the millimeter-wave wireless signals in a 60 GHz frequency band.
17. The method recited in claim 15 , wherein the transceiver comprises a cellular transceiver configured to transmit and receive the millimeter-wave wireless signals in one or more of a 28 GHz frequency band or a 39 GHz frequency band.
18. The method recited in claim 10 , wherein the shared supply node, the signal path, and the bypass and decoupling structure are provided in a wireless device configured to transmit and receive millimeter-wave wireless signals.
19. A passive filtering circuit, comprising:
an inductor having a first terminal connected to a shared supply node and a second terminal connected to gain stage circuitry; and
a capacitor having a first terminal connected to ground and a second terminal connected to the gain stage circuitry.
20. The passive filtering circuit recited in claim 19 , wherein the second terminal of the capacitor is further connected to the second terminal of the inductor.
21. The passive filtering circuit recited in claim 19 , wherein the inductor and the capacitor are configured to isolate the gain stage circuitry from a current flowing on a supply line coupling the inductor to the shared supply node.
22. The passive filtering circuit recited in claim 19 , incorporated into a wireless device configured to transmit and receive millimeter-wave wireless signals in one or more of a 28 GHz frequency band, a 39 GHz frequency band, or a 60 GHz frequency band.