Electronic damping of MEMS devices using a look-up table

A MEMS apparatus comprising:

• a) a MEMS array comprising a plurality of MEMS devices, each of the plurality of MEMS devices comprising:
• (i) a movable structure;
• and
• (ii) a motion stop;
• b) a plurality of signal sources coupled to the plurality of MEMS devices so as to be capable of supplying actuation signals for actuating the movable structure to impact the motion stop;
• c) at least one processor coupled to the plurality of signal sources to control the actuation signals;
• d) the at least one processor being configured such that each of the plurality of MEMS devices is provided with a corresponding custom actuation signal;
• e) a selector capable of selectively applying output signals from the plurality of signal sources to selected ones of the plurality of MEMS devices;
• f) a storage medium comprising a look-up table;
• g) wherein the look-up table comprises a custom damping coefficient for each of the plurality of MEMS devices;
• h) wherein the at least one processor is configured to retrieve a custom damping coefficient from the look-up table corresponding to a MEMS device selected for actuation;
• and
• i) wherein the at least one processor is coupled and configured to control the plurality of signal sources such that a damping portion of the custom actuation signal may be provided contemporaneously to multiple MEMS devices.

A MEMS apparatus comprising:

• a) a MEMS array comprising a plurality of MEMS devices;
• b) each of the plurality of MEMS devices comprising:
• (i) a first movable structure;
• and
• (ii) and a second structure;
• c) a signal supply means coupled to the plurality of MEMS devices so for supplying actuation signals for actuating the movable structure to impact the second structure;
• d) a processor means coupled to the signal supply means for controlling the actuation signals;
• and
• e) the processor means being configured such that each of the plurality of MEMS devices is provided with a corresponding custom actuation signal.

A method of electrically damping impacting structures for a plurality of MEMS devices, the method comprising:

• a) selecting an actuation signal comprising a portion for providing damping of an impact between a first and a second MEMS structure;
• b) applying the actuation signal to each of the plurality of MEMS devices comprising:
• (i) applying the selected signal to actuate the first structure to impact the second structure;
• (ii) varying a damping coefficient of the selected signal;
• and
• (iii) observing a settling time of the first structure in response to varied damping coefficients;
• c) selecting a custom damping coefficient for each of the plurality of MEMS devices based on the step of observing settling times of the first structure of each of the plurality of MEMS devices;
• d) storing the selected custom damping coefficient for each of the plurality of MEMS devices;
• e) programming at least one processor to construct a custom operating actuation signal for each of the first structures of the plurality of MEMS devices;
• and
• f) wherein programming the at least one processor comprises programming the at least one processor such that each custom operating actuation signal comprises the selected actuation signal having the stored custom damping coefficient from the storage device corresponding to a first MEMS structure being actuated.

A method for operating a plurality of MEMS devices comprising:

• a) applying a magnitude of a selected actuation signal equal to a first substantially constant magnitude to an actuator to cause a movable structure to begin to accelerate from a first position to impact a motion stop at a second position;
• b) decreasing the magnitude of the selected actuation signal in a first manner;
• c) varying at least one of a start time and a duration of the decreasing magnitude of the selected actuation signal;
• d) observing a settling time of the movable structure in response to the step of varying;
• e) ascertaining a value for the start times and the corresponding durations for each of the plurality of MEMS devices that provides substantially a best settling time for each of the MEMS devices based on the steps of varying and observing;
• f) ascertaining the value for the start times and the corresponding durations for each of the plurality of MEMS devices that provides substantially a best settling time for each of the MEMS devices;
• g) using the ascertained values for each of the plurality of MEMS devices and the selected actuation signal, controlling a signal source with a programmed processor to selectively apply the best value for operating actuation signal to the plurality of MEMS devices.