IGFET and tuning circuit
First Claim
Patent Images
1. A tuning circuit comprising:
- a first reactance;
a second reactance; and
an insulated gate field effect transistor having a gate arranged to receive a control signal, the first reactance being connected between the source of the field effect transistor and a first node and the second reactance having the same value as the first reactance and being connected between the drain of the field effect transistor and a second node; and
wherein the first and second nodes are arranged so as to experience a balanced ac signal and there being no circuit connection for grounding the source and drain of said transistor.
1 Assignment
0 Petitions
Accused Products
Abstract
A tuning circuit comprising a first reactance, a second reactance and a insulated gate field effect transistor having a gate arranged to receive a control signal. The first reactance is connected between the source of the field effect transistor and a first node. The second reactance has the same value as the first reactance and is connected between the drain of the field effect transistor and a second node. The first and second nodes are arranged so as to experience a balanced ac signal. Turning the field effect transistor on has the effect of making the first and second reactances effective in the circuit and vice versa.
14 Citations
31 Claims
-
1. A tuning circuit comprising:
-
a first reactance; a second reactance; and an insulated gate field effect transistor having a gate arranged to receive a control signal, the first reactance being connected between the source of the field effect transistor and a first node and the second reactance having the same value as the first reactance and being connected between the drain of the field effect transistor and a second node; and wherein the first and second nodes are arranged so as to experience a balanced ac signal and there being no circuit connection for grounding the source and drain of said transistor. - View Dependent Claims (2, 3, 4, 5)
-
-
6. A tuning circuit comprising:
-
a first reactance; a second reactance; and an insulated gate field effect transistor having a gate arranged to receive a control signal; the first reactance being connected between the source of the field effect transistor and a first node and the second reactance having the same value as the first reactance and being connected between the drain of the field effect transistor and a second node; wherein the first and second nodes are arranged so as to experience a balanced ac signal; and the insulated gate field effect transistor comprises source and drain regions within a surrounding region and gate electrode means provided over a channel or channels between said source and drain regions and over at least part of the boundary between said source and drain regions and said surrounding region, said surrounding region being provided with ground connection means for connection to an AC ground. - View Dependent Claims (7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17)
-
-
18. A resonant circuit including a tuning circuit, the tuning circuit comprising:
-
a first reactance; a second reactance; and an insulated gate field effect transistor having a gate arranged to receive a control signal; the first reactance being connected between the source of the field effect transistor and a first node and the second reactance having the same value as the first reactance and being connected between the drain of the field effect transistor and a second node; wherein the first and second nodes are arranged so as to experience a balanced ac signal; and the insulated gate field effect transistor comprises source and drain regions within a surrounding region and gate electrode means provided over a channel or channels between said source and drain regions and over at least part of the boundary between said source and drain regions and said surrounding region, said surrounding region being provided with ground connection means for connection to an AC ground. - View Dependent Claims (19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31)
-
Specification