Optical image stabilization actuator driver power distribution control
View Patent ↗Various embodiments provide an optical image stabilization circuit including a drive circuit having a power waveform generator and a power waveform conversion circuit. The power waveform generator generates a power waveform. The power waveform conversion circuit converts the power waveform to a power drive signal. An actuator is then driven by the power drive signal to move a lens accordingly and compensate for any movements and vibrations of a housing of the lens.
1. A device, comprising:
a lens;
an actuator configured to move the lens;
a position sensor configured to measure a position of the lens;
a gyroscope configured to measure movement of the device;
a controller configured to determine drive signal data based on the position of the lens and the movement of the device; and
a drive circuit configured to:
calculate a base amplitude value based on the drive signal data;
calculate a minimum non-zero amplitude value by shifting bits of the base amplitude value,
calculate a maximum non-zero amplitude value based on the minimum non-zero amplitude value,
calculate durations for the minimum non-zero amplitude value, the maximum non-zero amplitude value, and an intermediate non-zero amplitude value based on the drive signal data,
generate a waveform using the minimum, the maximum, and the intermediate non-zero amplitude values and the durations for the minimum, the maximum, and the intermediate non-zero amplitude values,
convert the waveform to a drive signal, and
drive the actuator to move the lens, the waveform including a plurality of cycles, each of plurality of cycles including the minimum, the maximum, and the intermediate non-zero amplitude values.
2. The device of claim 1 , wherein the drive circuit includes a digital to analog converter and a voltage to current converter circuit.
3. The device of claim 1 wherein the drive signal data includes a power input parameter that sets a total power value for the waveform.
4. The device of claim 3 wherein the drive circuit is configured to calculate an incremental amplitude value by parsing a bit range of the power input parameter, and to calculate the intermediate non-zero amplitude value based on the incremental amplitude value and the minimum non-zero amplitude value.
5. The device of claim 1 wherein the drive signal data includes a transition limit parameter that sets a maximum amount of change in amplitude between one time interval to a subsequent time interval for the waveform.
6. The device of claim 1 wherein the drive circuit is configured to:
calculate a timing value based on the drive signal data;
calculate a maximum amplitude output value length by shifting bits of the timing value, the maximum amplitude output value length indicating a time duration for the maximum non-zero amplitude value in each of the plurality of cycles; and
calculate a minimum amplitude output value length based on the maximum amplitude output value length, the minimum amplitude output value length indicating a time duration for the minimum non-zero amplitude value in each of the plurality of cycles.
7. A device, comprising:
a lens;
an actuator configured to move the lens;
a position sensor configured to measure a position of the lens;
a gyroscope configured to measure movement of the device;
a controller configured to calculate parameters based on the position of the lens and the movement of the device, the calculated parameters including:
a base amplitude value that is calculated based on the position of the lens and the movement of the device,
a minimum non-zero amplitude value that is calculated by shifting bits of the base amplitude value, and
a maximum non-zero amplitude value that is calculated based on the minimum non-zero amplitude value;
a power waveform generator configured to generate a waveform based on the calculated parameters, the waveform including a plurality of cycles, each of plurality of cycles including the minimum non-zero amplitude value, the maximum non-zero amplitude value, and an intermediate non-zero amplitude value;
a power waveform converter configured to convert the waveform to a to a drive signal; and
a drive circuit configured to drive the actuator with the drive signal to move the lens.
8. The device of claim 7 wherein the parameters includes the intermediate non-zero amplitude value for the waveform.
9. The device of claim 8 wherein the parameters includes timing values of the minimum, the maximum, and the intermediate non-zero amplitude values for the waveform.
10. The device of claim 7 wherein the parameters includes a power input parameter that sets a total power value for the waveform, and the controller is configured to calculate an incremental amplitude value by parsing a bit range of the power input parameter, and to calculate the intermediate non-zero amplitude value based on the incremental amplitude value and the minimum non-zero amplitude value.
11. The device of claim 7 wherein the parameters includes a power input parameter that sets a total power value for the waveform.
12. The device of claim 7 wherein the parameters includes a transition limit parameter that sets a maximum amount of change in amplitude between one time interval to a subsequent time interval for the waveform.
13. The device of claim 7 wherein the power waveform converter includes a digital to analog converter and a voltage to current converter.
14. The device of claim 7 wherein the power waveform converter is configured to dynamically adjust the voltage signal to minimize an offset error.
15. A device, comprising:
an actuator;
a waveform generator configured to:
receive drive signal data;
calculate a base amplitude value based on the drive signal data;
calculate a minimum non-zero amplitude value by shifting bits of the base amplitude value,
calculate a maximum non-zero amplitude value based on the minimum non-zero amplitude value,
calculate durations of the minimum non-zero amplitude value, the maximum non-zero amplitude value, and an intermediate non-zero amplitude value based on the drive signal data; and
generate a waveform based on the minimum, the maximum, and the intermediate non-zero amplitude values and durations of the minimum, the maximum, and the intermediate non-zero amplitude values, the waveform including a plurality of cycles, each of plurality of cycles including the minimum, the maximum, and the intermediate non-zero amplitude values;
a waveform converter configured to convert the waveform to a drive signal; and
a drive circuit configured to drive the actuator with the drive signal.
16. The device of claim 7 wherein the controller is configured to:
calculate a timing value based on the position of the lens and the movement of the device;
calculate a maximum amplitude output value length by shifting bits of the timing value, the maximum amplitude output value length indicating a time duration for the maximum non-zero amplitude value in each of the plurality of cycles; and
calculate a minimum amplitude output value length based on the maximum amplitude output value length, the minimum amplitude output value length indicating a time duration for the minimum non-zero amplitude value in each of the plurality of cycles.
17. The device of claim 15 wherein the drive signal data includes a power input parameter that sets a total power value for the waveform.
18. The device of claim 17 wherein the waveform generator is configured to calculate an incremental amplitude value by parsing a bit range of the power input parameter, and to calculate the intermediate non-zero amplitude value based on the incremental amplitude value and the minimum non-zero amplitude value.
19. The device of claim 15 wherein the drive signal data includes a transition limit parameter that sets a maximum amount of change in amplitude between one time interval to a subsequent time interval for the waveform.
20. The device of claim 15 wherein the waveform converter includes a digital to analog converter and a voltage to current converter.