1. A method of trimming a parameter of an integrated circuit including first and second conductors each of which can be incrementally adjusted to accomplish trimming of the parameter, the integrated circuit also including a first trim array including a plurality of weighted trim elements each having a corresponding bit number and each coupled to a corresponding interruptible link which determines whether that trim element is operatively coupled to the first conductor and a second trim array including a plurality of weighted trim elements each having the same bit number as a weighted trim element of the first trim array and each coupled to a corresponding interruptible link which determines whether that trim element is operatively coupled to the second conductor, the method comprising:
(a) measuring an initial value of the parameter;
(b) determining whether the parameter has a first relationship to a predetermined reference value;
(c) as long as the parameter has the first relationship to the predetermined reference value, repetitively interrupting a link of the first trim array having a bit number and decrementing the bit number to change the parameter in a first direction by weighted amounts corresponding to the bit number values until either all links of the first trim array have been interrupted or links of the first trim array have been interrupted to cause the parameter to become less than a first accuracy value;
(d) interrupting an interruptible link of the second trim array corresponding to the present bit number if step (c) determines that the present value of the parameter has the first relationship to the predetermined accuracy value; and
(e) if in step (d) all of the all links in the first trim array have not yet been interrupted, decrementing the bit number and repeating steps (b), (c), (d), and (e) until all of the all links of the first trim array have been interrupted.
2. The method of claim 1 wherein the integrated circuit includes an operational amplifier and wherein the parameter is an input offset voltage of the operational amplifier.
3. The method of claim 1 including setting an initial value of the bit number to the bit number of the most significant bit of the first trim array before performing step (c).
4. The method of claim 1 wherein each interruptible link includes a fuse, and interrupting of the interruptible link includes blowing the fuse.
5. The method of claim 1 wherein each interruptible link includes a laser-cuttable link, and interrupting of the interruptible link includes laser-cutting the laser-cuttable link.
6. The method of claim 1 wherein the predetermined accuracy value has a magnitude equal to the magnitude of half of the accuracy value of a least significant bit of the first trim array.
7. The method of claim 1 including operating a processor in order to perform steps (a) through (e).
8. The method of claim 1 wherein the trimming of the parameter is complete if in step (d) it is determined that all links in the first trim array have been interrupted.
9. The method of claim 1 including operating a processor to perform steps (a)\u2013(e).
10. A method of trimming a parameter of an integrated circuit including first and second conductors each of which can be incrementally adjusted to accomplish trimming of the parameter, the integrated circuit also including a first trim array including a plurality of weighted trim elements each having a corresponding bit number and each coupled to a corresponding interruptible link which determines whether that trim element is operatively coupled to the first conductor and a second trim array including a plurality of weighted trim elements each having the same bit number as a weighted trim element of the first trim array and each coupled to a corresponding interruptible link which determines whether that trim element is operatively coupled to the second conductor, the method comprising:
(a) measuring an initial value of the parameter,
(b) determining whether the parameter exceeds a predetermined reference value;
(c) as long as the parameter exceeds the predetermined reference value, repetitively interrupting a link of the first trim array having a bit number and decrementing the bit number to decrease the parameter by weighted amounts corresponding to the bit number values until either all links of the first trim array have been interrupted or enough links of the first trim array have been interrupted to cause the parameter to become less than a first accuracy value;
(d) interrupting an interruptible link of the second trim array corresponding to the present bit number if step (c) determines that the present value of the parameter is less than the first accuracy value; and
(e) if in step (d) all of the all links in the first trim array have not yet been interrupted, decrementing the bit number and repeating steps (b), (c), (d), and (e) until all all of the all links of the first trim array have been interrupted.
11. The method of claim 10 wherein, if in step (b) the parameter does not exceed the first reference value, then performing the steps of
(f) as long as the parameter is less than the predetermined reference value, repetitively interrupting a link of the second trim array having the present bit number and decrementing the bit number to increase the parameter by weighted amounts corresponding to the bit number values until either all links of the second trim array have been interrupted or enough links of the second trim array have been interrupted to cause the parameter to exceed a second accuracy value;
(g) interrupting an interruptible link of the first trim array corresponding to the present bit number if step (f) determines that the present value of the parameter exceeds the second accuracy value; and
(h) if in step (g) all of the all links in the first trim array have not yet been interrupted, decrementing the present bit number and repeating steps (f), (g), and (h) until all of the all links of the first trim array have been interrupted.
12. The method of claim 10 wherein the integrated circuit includes an operational amplifier and wherein the parameter is an input offset voltage of the operational amplifier.
13. The method of claim 10 including setting an initial value of the bit number to the bit number of the most significant bit of the first trim array before performing step (c).
14. The method of claim 10 wherein each interruptible link includes a fuse, and interrupting of the interruptible link includes blowing the fuse.
15. The method of claim 10 wherein each interruptible link includes a laser-cuttable link, and interrupting of the interruptible link includes laser-cutting the laser-cuttable link.
16. The method of claim 10 wherein the predetermined accuracy value has a magnitude equal to the magnitude of half of the accuracy value of a least significant bit of the first trim array.
17. The method of claim 10 including operating a processor in order to perform steps (a) through (e).
18. The method of claim 10 wherein the trimming of the parameter is complete if in step (d) it is determined that all links in the first trim array have been interrupted.
19. The method of claim 10 including operating a processor to perform steps (a)\u2013(e).
20. A method of trimming a parameter of an integrated circuit including first and second conductors each of which can be incrementally adjusted to accomplish trimming of the parameter, the integrated circuit also including a first trim array including a plurality of weighted trim elements each having a corresponding bit number and each coupled to a corresponding interruptible link which determines whether that trim element is operatively coupled to the first conductor and a second trim array including a plurality of weighted trim elements each having the same bit number as a weighted trim element of the first trim array and each coupled to a corresponding interruptible link which determines whether that trim element is operatively coupled to the second conductor, the method comprising:
(a) measuring an initial value of the parameter;
(b) determining whether the parameter exceeds a predetermined reference value;
(c) interrupting a link of the first trim array having a bit number to decrease the parameter by a weighted amount corresponding to the bit number if step (b) determines that the parameter exceeds the predetermined reference value;
(d) measuring a present value of the parameter and determining if the present value of the parameter exceeds a first accuracy value;
(e) determining whether the bit number is a LSB bit number of the first and second trim arrays if step (d) determines that the present value of the parameter does not exceed the first accuracy value;
(f) decrementing the bit number and repeating steps (c), (d), (e), and f) for the decremented bit number if the bit number is not the LSB bit number, the trimming of the parameter being complete if the present bit number is equal to the LSB bit number;
(g) interrupting an interruptible link of the second trim array corresponding to the present bit number if step (d) determines that the present value of the parameter is less than the first accuracy value, the trimming of the parameter being complete if the bit number is equal to the LSB bit number;
(h) decrementing the bit number if it is not equal to the LSB bit number; and
(i) measuring the value of the parameter and repeating steps (c), (d), (e) and (f) if the present bit number is equal to the LSB bit number.
21. The method of claim 20 wherein the integrated circuit includes an operational amplifier and wherein the parameter is an input offset voltage of the operational amplifier.
22. The method of claim 20 including setting an initial value of the bit number to the bit number of a most significant bit of the first trim array before performing step (c).
23. The method of claim 20 wherein each interruptible link includes a fuse, and interrupting of the interruptible link includes blowing the fuse.
24. The method of claim 20 wherein each interruptible link includes a laser-cuttable link, and interrupting of the interruptible link includes laser-cutting the laser-cuttable link.
25. The method of claim 20 wherein the predetermined accuracy value has a magnitude equal to half of the magnitude of the accuracy value of a least significant bit of the first trim array.
26. The method of claim 20 including operating a processor in order to perform steps (a) through (e).
27. The method of claim 20 including operating a processor to perform steps (a)\u2013(l).
28. A system for trimming a parameter of an integrated circuit including first and second conductors each of which can be incrementally adjusted to accomplish trimming of the parameter, the integrated circuit also including a first trim array including a plurality of weighted trim elements each having a corresponding bit number and each coupled to a corresponding interruptible link which determines whether that trim element is operatively coupled to the first conductor and a second trim array including a plurality of weighted trim elements each having the same bit number as a corresponding weighted trim element of the first trim array and each coupled to a corresponding interruptible link which determines whether that trim element is operatively coupled to the second conductor, the method comprising:
(a) means for measuring an initial value of the parameter;
(b) means for determining whether the parameter has a first relationship to a predetermined reference value;
(c) means for repetitively interrupting a link of the first trim array having a bit number and decrementing the bit number to change the parameter in a first direction by weighted amounts corresponding to the bit number values until either all links of the first trim array have been interrupted or enough links of the first trim array have been interrupted to cause the parameter to have a second relationship a predetermined accuracy value as long as the parameter has the first relationship to the predetermined reference value;
(d) means for interrupting an interruptible link of the second trim array corresponding to the present bit number if the present value of the parameter has the second relationship to the predetermined accuracy value to change the parameter to a value such that its does not have the second relationship to the predetermined accuracy value; and
(e) means for repeating the functions restated in elements s (b), (c), and (d) until all of the all links of the first trim array have been interrupted if all of the all links in the first trim array have not yet been interrupted.
29. The system of claim 28 wherein each interruptible link includes a fuse, and wherein interrupting of the interruptible link includes blowing the fuse, the integrated circuit including fuse blowing logic control means coupled to a processor for selecting and blowing fuses.
30. The system of claim 28 wherein each interruptible link includes a laser-cuttable link, and wherein interrupting of the interruptible link includes controlling a laser system to precisely align a laser beam of the laser system with the laser-cuttable link and firing the laser beam.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A method for detecting speech activity, comprising:
directing an ultrasonic signal at a face of a speaker over time;
acquiring a Doppler signal of the ultrasonic signal after reflection by the face;
measuring an energy in the Doppler signal over time; and
comparing the energy over time to a predetermined threshold to detect speech activity of the speaker.
2. The method of claim 1, further comprising:
frequency demodulating the Doppler signal before the measuring.
3. The method of claim 2, in which the frequency demodulation is into a range of frequency bands.
4. The method of claim 1, further comprising:
sampling the Doppler signal; and
partitioning the samples into frames before the measuring.
5. The method of claim 4, in which the frames overlap in time.
6. The method of claim 2, further comprising:
extracting discrete Fourier transform (DFT) coefficients from the demodulated Doppler signal; and
measuring the energy from the DFT coefficients.
7. The method of claim 1, further comprising:
filtering the Doppler signal to smooth the energy before the measuring.
8. The method of claim 7, further comprising:
determining a medium of the energy over time before the comparing using the filtering.
9. The method of claim 1, further comprising:
acquiring concurrently an audio signal while acquiring the Doppler signal; and
processing the audio signal only while detecting the speech activity.
10. The method of claim 1, further comprising:
heterodyning the Doppler signal before the measuring.
11. The method of claim 1, in which the ultrasonic signal is spatially narrow beam.
12. The method of claim 11, in which the ultrasonic signal has a bandwidth corresponding to a bandwidth of the demodulated Doppler signal.
13. The method of claim 9, in which the acquiring is performed with colocated sensors.
14. The method of claim 1, in which a bandwidth of the ultrasonic signal corresponds to a bandwidth of frequencies at which articulator of the face move while speaking.
15. The method of claim 2, in which the energy is obtained from an amplitude of the demodulated Doppler signal.
16. The method of claim 2, in which the demodulating is similar to spectral-decomposition of the ultrasonic signal.
17. The method of claim 1, further comprising:
sampling the ultrasonic signal to obtain overlapping frames.
18. A system for detecting speech activity, comprising:
a transmitter configured to direct an ultrasonic signal at a face of a speaker;
a receiver configured to acquire a Doppler signal of the ultrasonic signal after reflection by the face;
means for measuring an energy in the Doppler signal; and
means for comparing the energy to a threshold to detect speech activity.
19. An apparatus for detecting speech activity, comprising:
an emitter configured to direct an ultrasonic signal at a face of a speaker;
a transducer configured to acquire a Doppler signal of the ultrasonic signal after reflection by the face;
a microphone configured to acquire an audio signal; and
means coupled to the transducer and microphone to detect speech activity in the audio signal based on an energy of the Doppler signal.
20. The apparatus of claim 19, in which the emitter, transducer and microphone are colocated.