Abstract:
Embodiments disclosed herein generally relate to power amplifier matching circuits used for matching impedance and harmonic control in a device, such as a cellular phone. In one example, a power amplifier matching circuit includes two DVCs, four inductors, a transistor, and a capacitor. Utilizing the two DVCs, the impedance matching ratio and the center frequency of the circuit are capable of adjustment as needed. Moreover, the inclusion of the two DVCs may also prevent harmonic frequencies from undesirably passing through the power amplifier matching circuit to the antenna of a cellular device. The power amplifier matching circuit may be used in conjunction with an amplifier, where the output of the amplifier is proportional to the current in the circuit.
Abstract:
The present invention generally relates to a MEMS device and a method of manufacture thereof. The RF electrode, and hence, the dielectric layer thereover, has a curved upper surface that substantially matches the contact area of the bottom surface of the movable plate. As such, the movable plate is able to have good contact with the dielectric layer and thus, good capacitance is achieved.
Abstract:
The present disclosure generally relates to a device having a variable frequency filter that rejects harmonics generated by a variable reactance device. The variable frequency filter may be coupled to the antenna and the variable reactance device. The filter includes a variable capacitor and an inductor coupled together as a resonant circuit. The filter may be used in cellular technology to prevent harmonic frequencies that are created by another variable reactance device from reaching the antenna of the cellular device. Furthermore, the filter can reflect any receiving frequencies from the antenna and prevent the receiving frequencies from passing through.
Abstract:
The present invention generally relates to a mechanism for testing a MEMS hysteresis. A power management circuit may be coupled to the electrodes that cause the movable plate that is disposed between the electrodes in a MEMS device to move. The power management circuit may utilize a charge pump, a comparator and a resistor ladder.
Abstract:
A variable capacitor (300) comprises cells (200, 400) that have an RF electrode (202, 402) coupled to a bond pad (30). Each cell comprises a plurality of MEMS devices (100) the capacitance of which can be changed by means of a movable electrode. The MEMS devices are placed in a sealed cavity of the cell and are arranged next to each other along the length of the RF electrode of the cell. The RF electrode of each cell can be trimmed so as to obtain an RF line (402) and a further ground electrode (404) and so as to scale the RF capacitance of the cell without impacting the mechanical performance of the MEMS cells. Each cell has the same control capacitance irrespective of the RF capacitance. This allows each cell to use the same isolation resistor required for RF operation and thus each cell has the same parasitic capacitance. This allows the CMOS control circuit to be optimized and the dynamic performance of the cells to be matched.
Abstract:
The present invention generally relates to a MEMS device and a method of manufacture thereof. The RF electrode, and hence, the dielectric layer thereover, has a curved upper surface that substantially matches the contact area of the bottom surface as of the movable plate. As such, the movable plate is able to have good contact with the dielectric layer and thus, good capacitance is achieved.
Abstract:
The present invention generally relates to methods for increasing the lifetime of MEMS devices by reducing the number of movements of a switching element in the MEMS device. Rather than returning to a ground state between cycles, the switching element can remain in the same state if both cycles necessitate the same capacitance. For example, if in both a first and second cycle, the switching element of the MEMS device is in a state of high capacitance the switching element can remain in place between the first and second cycle rather than move to the ground state. Even if the polarity of the capacitance is different in successive cycles, the switching element can remain in place and the polarity can be switched. Because the switching element remains in place between cycles, the switching element, while having the same finite number of movements, should have a longer lifetime.
Abstract:
The present invention generally relates to techniques and structures that cancel or mitigate RF coupling from the RF circuit to the silicon die. To cancel or mitigate the RF coupling, a conductive coating may be formed over the RF-MEMS device. The conductive coating may be coupled to the die. Alternatively, the conductive coating may be coupled to the die through the RF-MEMS by having a through silicon via. Another manner for cancelling or mitigating RF coupling is to have no conductive traces located on the front side of the PCB.
Abstract:
The current disclosure shows how to make a fast switching array of mirrors for projection displays. Because the mirror does not have a via in the middle connecting to the underlying spring support, there is an improved contrast ratio that results from not having light scatter off the legs or vias like existing technologies. Because there are no supporting contacts, the mirror can be made smaller making smaller pixels that can be used to make higher density displays. In addition, because there is not restoring force from any supporting spring support, the mirror stays in place facing one or other direction due to adhesion. This means there is no need to use a voltage to hold the mirror in position. This means that less power is required to run the display.
Abstract:
The present invention generally relates to methods for increasing the lifetime of MEMS devices by reducing the number of movements of a switching element in the MEMS device. Rather than returning to a ground state between cycles, the switching element can remain in the same state if both cycles necessitate the same capacitance. For example, if in both a first and second cycle, the switching element of the MEMS device is in a state of high capacitance the switching element can remain in place between the first and second cycle rather than move to the ground state. Even if the polarity of the capacitance is different in successive cycles, the switching element can remain in place and the polarity can be switched. Because the switching element remains in place between cycles, the switching element, while having the same finite number of movements, should have a longer lifetime.