SYSTEMS, DEVICES, AND METHODS FOR DRIVING AN ANALOG INTERFEROMETRIC MODULATOR UTILIZING DC COMMON WITH RESET
A display apparatus comprising an array of electromechanical display elements and a driver circuit coupled to the array is provided. The driver circuit is configured to apply a DC voltage to a first stationary electrode of the display element and adjust a bias voltage applied to a second stationary electrode of the display element from a first bias voltage to a second bias voltage before a reset period. The driver circuit is further configured to apply a first reset voltage to a movable electrode of the display element during the reset period, apply a write voltage to the movable electrode during a charging period to charge the movable electrode with a charge Q defined at least in part by the write voltage, and adjust the bias voltage applied to the second stationary electrode from the second bias voltage to a third bias voltage during a bias period.
1 . A method of writing image data to an electromechanical display element including a first stationary electrode, a second stationary electrode, and a movable electrode, the method comprising:
applying a direct current (DC) voltage to the first stationary electrode of the electromechanical display element;
adjusting a bias voltage applied to the second stationary electrode of the electromechanical display element from a first bias voltage to a second bias voltage before a reset period;
applying a first reset voltage to the movable electrode of the electromechanical display element during the reset period;
applying a write voltage to the movable electrode during a charging period to charge the movable electrode with a charge Q defined at least in part by the write voltage; and
adjusting the bias voltage applied to the second stationary electrode from the second bias voltage to a third bias voltage during a bias period.
2 . The method of claim 1 , further comprising applying a second reset voltage to the movable electrode during the reset period.
3 . The method of claim 2 , wherein the applied second reset voltage is deasserted a first amount of time before the charging period, the first amount of time equal to approximately 1 to 10 times a period to write an entire row of electromechanical display elements.
4 . The method of claim 1 , wherein adjusting the bias voltage from the second bias voltage to the third bias voltage occurs before the charging period.
5 . The method of claim 1 , wherein adjusting the bias voltage from the second bias voltage to the third bias voltage occurs after the charging period.
6 . The method of claim 1 , wherein the DC voltage, the reset voltage, and the second bias voltage are substantially zero volts.
7 . The method of claim 1 , wherein the first bias voltage and the third bias voltage are substantially equal in magnitude and opposite in polarity.
8 . The method of claim 1 , wherein during the reset period, the movable electrode is placed in a reset state.
9 . The method of claim 1 , wherein the charging period occurs a second amount of time after the reset period, the second amount of time equal to approximately 10 to 100 times a period to write an entire row of electromechanical display elements.
10 . A display apparatus comprising:
an array of electromechanical display elements, each electromechanical display element including a first stationary electrode, a second stationary electrode, and a movable electrode;
a driver circuit coupled to the array and configured to:
apply a DC voltage to the first stationary electrode of the electromechanical display element;
adjust a bias voltage applied to the second stationary electrode of the electromechanical display element from a first bias voltage to a second bias voltage before a reset period;
apply a first reset voltage to the movable electrode of the electromechanical display element during the reset period;
apply a write voltage to the movable electrode during a charging period to charge the movable electrode with a charge Q defined at least in part by the write voltage; and
adjust the bias voltage applied to the second stationary electrode from the second bias voltage to a third bias voltage during a bias period.
11 . The display apparatus of claim 10 , wherein the driver circuit is further configured to apply a second reset voltage to the movable electrode during the reset period.
12 . The display apparatus of claim 11 , wherein the driver circuit is further configured to deassert the applied second reset voltage a first amount of time before the charging period, the first amount of time equal to approximately 1 to 10 times a period to write an entire row of electromechanical display elements.
13 . The display apparatus of claim 10 , wherein the driver circuit is configured to adjust the bias voltage from the second bias voltage to the third bias voltage before the charging period.
14 . The display apparatus of claim 10 , wherein the driver circuit is configured to adjust the bias voltage from the second bias voltage to the third bias voltage after the charging period.
15 . The display apparatus of claim 10 , wherein the DC voltage, the reset voltage, and the second bias voltage are substantially zero volts.
16 . The display apparatus of claim 10 , wherein the first bias voltage and the third bias voltage are substantially equal in magnitude and opposite in polarity.
17 . The display apparatus of claim 10 , wherein the movable electrode is positioned between the first and second stationary electrodes.
18 . The display apparatus of claim 10 , wherein during the reset period, the driver circuit is configured to place the movable electrode in a reset state.
19 . The display apparatus of claim 10 , wherein the driver circuit is configured to perform the charging period a second amount of time after the reset period, the second amount of time equal to approximately 10 to 100 times a period to write an entire row of electromechanical display elements.
20 . A display apparatus comprising:
an array of electromechanical display elements, each electromechanical display element including a first stationary electrode, a second stationary electrode, and a movable electrode;
means for applying a DC voltage to the first stationary electrode of the electromechanical display element;
means for adjusting a bias voltage applied to the second stationary electrode of the electromechanical display element from a first bias voltage to a second bias voltage before a reset period;
means for applying a first reset voltage to the movable electrode of the electromechanical display element during the reset period;
means for applying a write voltage to the movable electrode during a charging period to charge the movable electrode with a charge Q defined at least in part by the write voltage; and
means for adjusting the bias voltage applied to the second stationary electrode from the second bias voltage to a third bias voltage during a bias period.
21 . The display apparatus of claim 20 , further comprising means for applying a second reset voltage to the movable electrode during the reset period.
22 . The display apparatus of claim 21 , wherein the means for applying the second reset voltage is configured to deassert the applied second reset voltage a first amount of time before the charging period, the first amount of time equal to approximately 1 to 10 times a period to write an entire row of electromechanical display elements.
23 . The display apparatus of claim 20 , wherein the means for adjusting the bias voltage from a first bias voltage to a second bias voltage is configured to adjust before the charging period.
24 . The display apparatus of claim 20 , wherein the means for adjusting the bias voltage from a first bias voltage to a second bias voltage is configured to adjust after the charging period.
25 . The display apparatus of claim 20 , wherein the DC voltage, the reset voltage, and the second bias voltage are substantially zero volts.