Digitally controlled high Q factor capacitor
View Patent ↗A control circuit and a conversion circuit. The control circuit may be configured to generate an analog control signal in response to a digital control signal. The conversion circuit may be configured to generate a capacitance signal in response to the analog control signal.
1. An apparatus comprising:
a control circuit configured to generate an analog control signal in response to a digital control signal, wherein said control circuit comprises a digital interface circuit and a digital-to-analog converter circuit; and
a conversion circuit configured to generate a capacitance signal in response to said analog control signal, wherein said digital interface circuit comprises a plurality of resistors each configured to be switched in response to said analog control signal.
2. The apparatus according to claim 1 , wherein said control circuit generates a plurality of said analog control signals.
3. The apparatus according to claim 1 , wherein said conversion circuit generates a plurality of said capacitance signals.
4. The apparatus according to claim 1 , wherein said capacitance signal is usable by an application circuit external to said apparatus.
5. The apparatus according to claim 4 , wherein said control circuit further responds to an input signal is received from said application circuit.
6. The apparatus according to claim 1 , wherein said conversion circuit further comprises a varactor diode.
7. The apparatus according to claim 1 , wherein said control circuit further comprises an oscillator circuit.
8. The apparatus according to claim 1 , further comprising:
a plurality of said control circuits each configured to generate one of a plurality of analog control signals; and
a plurality of said conversion circuits each configured to generate one of a plurality of said capacitance signals.
9. The apparatus according to claim 1 , wherein said digital control signal comprises a multi-bit digital word.
10. The apparatus according to claim 1 , wherein said digital control signal comprises a serial digital signal.
11. The apparatus according to claim 1 , wherein said control circuit comprises a digital interface circuit and a digital-to-analog converter circuit.
12. The apparatus according to claim 11 , wherein a plurality of switches each select one of said plurality of resistors in response to a selected one of a plurality of voltage points on a plurality of bond pads.
13. An apparatus comprising:
means for generating an analog control signal in response to a digital control signal, wherein said generating means comprises a digital interface circuit and a digital-to-analog converter circuit; and
means for generating a capacitance signal in response to said analog control signal, wherein said digital interface circuit comprises a plurality of resistors configured to be switched in response to said analog control signal.
14. A method for digitally controlling a capacitance comprising the steps of:
(A) generating an analog control signal in response to a digital control signal, wherein said control circuit comprises a digital interface circuit and a digital-to-analog converter circuit; and
(B) generating a capacitance signal in response to said analog control signal, wherein said digital interface circuit comprises a plurality of resistors configured to be switched in response to said analog control signal.
15. The apparatus according to claim 13 , wherein a plurality of switches each select one of said plurality of resistors in response to a selected one of a plurality of voltage points on a plurality of bond pads.
16. The method according to claim 14 , further comprising the step of:
selecting one of said plurality of resistors in response to a selected one of a plurality of voltage points on a plurality of bond pads.