Abstract: A memory device including a base semiconductor die, conductive terminals, memory dies, an insulating encapsulation and a buffer cap is provided. The conductive terminals are disposed on a first surface of the base semiconductor die. The memory dies are stacked over a second surface of the base semiconductor die, and the second surface of the base semiconductor die is opposite to the first surface of the base semiconductor die. The insulating encapsulation is disposed on the second surface of the base semiconductor die and laterally encapsulates the memory dies. The buffer cap covers the first surface of the base semiconductor die, sidewalls of the base semiconductor die and sidewalls of the insulating encapsulation. A package structure including the above- mentioned memory device is also provided.

Abstract: A memory device including a base semiconductor die, conductive terminals, memory dies, an insulating encapsulation and a buffer cap is provided. The conductive terminals are disposed on a first surface of the base semiconductor die. The memory dies are stacked over a second surface of the base semiconductor die, and the second surface of the base semiconductor die is opposite to the first surface of the base semiconductor die. The insulating encapsulation is disposed on the second surface of the base semiconductor die and laterally encapsulates the memory dies. The buffer cap covers the first surface of the base semiconductor die, sidewalls of the base semiconductor die and sidewalls of the insulating encapsulation. A package structure including the above-mentioned memory device is also provided.

Abstract: A microelectromechanical system (MEMS) gyroscope includes a driving mass and a driving circuit that operates to drive the driving mass in a mechanical oscillation at a resonant drive frequency. An oscillator generates a system clock that is independent of and asynchronous to the resonant drive frequency. A clock generator circuit outputs a first clock and a second clock that are derived from the system clock. The drive loop of the driving circuit including an analog-to-digital converter (ADC) circuit that is clocked by the first clock and a digital signal processing (DSP) circuit that is clocked by the second clock.

Abstract: A microelectromechanical system (MEMS) gyroscope includes a driving mass and a driving circuit that operates to drive the driving mass in a mechanical oscillation at a resonant drive frequency. An oscillator generates a system clock that is independent of and asynchronous to the resonant drive frequency. A clock generator circuit outputs a first clock and a second clock that are derived from the system clock. The drive loop of the driving circuit including an analog-to-digital converter (ADC) circuit that is clocked by the first clock and a digital signal processing (DSP) circuit that is clocked by the second clock.

Abstract: A microelectromechanical system (MEMS) gyroscope includes a driving mass and a driving circuit that operates to drive the driving mass in a mechanical oscillation at a resonant drive frequency. An oscillator generates a system clock that is independent of and asynchronous to the resonant drive frequency. A clock generator circuit outputs a first clock and a second clock that are derived from the system clock. The drive loop of the driving circuit including an analog-to-digital converter (ADC) circuit that is clocked by the first clock and a digital signal processing (DSP) circuit that is clocked by the second clock.

Abstract: A microelectromechanical system (MEMS) gyroscope includes a driving mass and a driving circuit that operates to drive the driving mass in a mechanical oscillation at a resonant drive frequency. An oscillator generates a system clock that is independent of and asynchronous to the resonant drive frequency. A clock generator circuit outputs a first clock and a second clock that are derived from the system clock. The drive loop of the driving circuit including an analog-to-digital converter (ADC) circuit that is clocked by the first clock and a digital signal processing (DSP) circuit that is clocked by the second clock.

Abstract: A drive signal is applied to a MEMS gyroscope having several intrinsic resonant modes. Frequency and amplitude of mechanical oscillation in response to the drive signal is sensed. At startup, the drive signal frequency is set to a kicking frequency offset from a resonant frequency corresponding to a desired one of the intrinsic resonant modes. In response to sufficient sensed amplitude of mechanical oscillation at the kicking frequency, a frequency tracking process is engaged to control the frequency for the drive signal to sustain mechanical oscillation at the frequency of the desired one of the plurality of intrinsic resonant modes as the oscillation amplitude increases. When the increasing amplitude of the mechanical oscillation exceeds a threshold, a gain control process is used to exercise gain control over the applied drive signal so as to cause the amplitude of mechanical oscillation to match a further threshold. At that point start-up terminates.

Abstract: A microelectromechanical system (MEMS) gyroscope includes a driving mass and a driving circuit that operates to drive the driving mass in a mechanical oscillation at a resonant drive frequency. An oscillator generates a system clock that is independent of and asynchronous to the resonant drive frequency. A clock generator circuit outputs a first clock and a second clock that are derived from the system clock. The drive loop of the driving circuit including an analog-to-digital converter (ADC) circuit that is clocked by the first clock and a digital signal processing (DSP) circuit that is clocked by the second clock.

Abstract: A drive signal is applied to a MEMS gyroscope having several intrinsic resonant modes. Frequency and amplitude of mechanical oscillation in response to the drive signal is sensed. At startup, the drive signal frequency is set to a kicking frequency offset from a resonant frequency corresponding to a desired one of the intrinsic resonant modes. In response to sufficient sensed amplitude of mechanical oscillation at the kicking frequency, a frequency tracking process is engaged to control the frequency for the drive signal to sustain mechanical oscillation at the frequency of the desired one of the plurality of intrinsic resonant modes as the oscillation amplitude increases. When the increasing amplitude of the mechanical oscillation exceeds a threshold, a gain control process is used to exercise gain control over the applied drive signal so as to cause the amplitude of mechanical oscillation to match a further threshold. At that point start-up terminates.

Abstract: A control circuit for controlling the rotational speed of a fan may include a memory element to store operating data corresponding to an operational profile of the fan defined by RPM (revolutions per minute) versus temperature, with the operating data comprising a respective temperature value and a respective RPM value for each respective operating point representing a change in slope of a function that corresponds to the operational profile of the fan. A processing unit may receive a present temperature value, retrieve the operating data from the storage unit, and identify a pair of consecutive operating points corresponding to the present temperature. The processing unit may calculate a desired RPM value corresponding to the present temperature value by performing linear interpolation between the pair of consecutive operating points, and provide the desired RPM value to a closed-loop fan controller to control the fan according to the desired RPM value.

Abstract: A control circuit for controlling the rotational speed of a fan may include a memory element to store operating data corresponding to an operational profile of the fan defined by RPM (revolutions per minute) versus temperature, with the operating data comprising a respective temperature value and a respective RPM value for each respective operating point representing a change in slope of a function that corresponds to the operational profile of the fan. A processing unit may receive a present temperature value, retrieve the operating data from the storage unit, and identify a pair of consecutive operating points corresponding to the present temperature. The processing unit may calculate a desired RPM value corresponding to the present temperature value by performing linear interpolation between the pair of consecutive operating points, and provide the desired RPM value to a closed-loop fan controller to control the fan according to the desired RPM value.

Abstract: A control circuit for controlling the rotational speed of a fan may include a memory element to store operating data corresponding to an operational profile of the fan defined by RPM (revolutions per minute) versus temperature, with the operating data comprising a respective temperature value and a respective RPM value for each respective operating point representing a change in slope of a function that corresponds to the operational profile of the fan. A processing unit may operate to receive a present temperature value, retrieve the operating data from the storage unit, and identify a pair of consecutive operating points such that the present temperature value is greater than a lower respective temperature value of the pair of consecutive operating points, and lower than a higher respective temperature value of the pair of consecutive operating points.

Abstract: A fan driver circuit for powering a fan with a linear voltage may be designed using digital design techniques, resulting in a testable, accurate circuit on a smaller die size. The fan driver circuit may be configured to receive a digital control signal, which may be a sequence of numeric values, e.g. multiple-bit binary numbers, each indicative of a desired present rotational speed of the fan. The fan driver circuit may be implemented using a digital modulator, e.g. a delta-sigma modulator, with a simple low-pass filter, e.g. an RC-filter at the output, and may use oversampling based on a system clock, to shift in-band noise to out-of-band frequencies, and digital interpolation to filter out unwanted images from the upsampled digital control signal. The delta-sigma modulator may be constructed as a first-order delta-sigma modulator using an error-feedback structure to reduce die size.

Abstract: A control circuit for controlling the rotational speed of a fan may include a memory element to store operating data corresponding to an operational profile of the fan defined by RPM (revolutions per minute) versus temperature, with the operating data comprising a respective temperature value and a respective RPM value for each respective operating point representing a change in slope of a function that corresponds to the operational profile of the fan. A processing unit may operate to receive a present temperature value, retrieve the operating data from the storage unit, and identify a pair of consecutive operating points such that the present temperature value is greater than a lower respective temperature value of the pair of consecutive operating points, and lower than a higher respective temperature value of the pair of consecutive operating points.

Abstract: A fan driver circuit for powering a fan with a linear voltage may be designed using digital design techniques, resulting in a testable, accurate circuit on a smaller die size. The fan driver circuit may be configured to receive a digital control signal, which may be a sequence of numeric values, e.g. multiple-bit binary numbers, each indicative of a desired present rotational speed of the fan. The fan driver circuit may be implemented using a digital modulator, e.g. a delta-sigma modulator, with a simple low-pass filter, e.g. an RC-filter at the output, and may use oversampling based on a system clock, to shift in-band noise to out-of-band frequencies, and digital interpolation to filter out unwanted images from the upsampled digital control signal. The delta-sigma modulator may be constructed as a first-order delta-sigma modulator using an error-feedback structure to reduce die size.

Abstract: An impedance network, which includes at least one end terminal, a wiper terminal, a center impedance element, and a first plurality of impedance elements. The wiper terminal provides a tap position at a selected impedance value of the impedance network, selectable at a specified increment value. The first plurality of impedance elements is configured to reduce resistance variation during switching from one tap position to another tap position. The first plurality of impedance element is connected in series in a mirrored configuration about the center impedance element.

Abstract: An impedance network, which includes at least one end terminal, a wiper terminal, a center impedance element, and a first plurality of impedance elements. The wiper terminal provides a tap position at a selected impedance value of the impedance network, selectable at a specified increment value. The first plurality of impedance elements is configured to reduce resistance variation during switching from one tap position to another tap position. The first plurality of impedance elements is connected in series in a mirrored configuration about the center impedance element.

Abstract: An impedance network, which includes at least one end terminal, a wiper terminal, a center impedance element, and a first plurality of impedance elements. The wiper terminal provides a tap position at a selected impedance value of the impedance network, selectable at a specified increment value. The first plurality of impedance elements is configured to reduce resistance variation during switching from one tap position to another tap position. The first plurality of impedance elements is connected in series in a mirrored configuration about the center impedance element.

Abstract: A conjugate vaccine for Nontypeable Haemophilus influenzae comprising lipooligosaccharide from which esterified fatty acids have been removed conjugated to an immunogenic carrier. The vaccine is useful for prevention of otitis media and respiratory infections in mammals.

Abstract: An impedance network, which includes at least one end terminal, a wiper terminal, a center impedance element, and a first plurality of impedance elements. The wiper terminal provides a tap position at a selected impedance value of the impedance network, selectable at a specified increment value. The first plurality of impedance elements is configured to reduce resistance variation during switching from one tap position to another tap position. The first plurality of impedance elements is connected in series in a mirrored configuration about the center impedance element.