Abstract in simplified Chinese:本发明揭示一种时钟同步化器,及包含该时钟同步化器之时钟与数据回复设备,与对应之时脉同步化方法。该时钟同步化器包含一弹性缓冲器。一被接收之时脉信号被使用以将数据依时脉存入缓冲器中,并且一本地产生的时脉被使用以将数据依时脉自该缓冲器取出。该本地时脉使用一锁相回路电路(PLL)被合成,并且来自弹性缓冲器之一充填位准信号被使用以控制本地时钟频率而维持所需的平均数据数量于该缓冲器中,因而实现该被接收时脉和本地时脉的同步化。于较佳实施例中,该充填位准信号被使用以控制锁相回路电路之回授路线中一可变除频器,其被供应高稳定的参考信号。一被同步化且低抖动之本地时脉因此被产生。最好是,该弹性缓冲器采用相对地宽之字组宽度的计数器,以及大量被降低深度之一存储数组,读取和写入指示器仅由字组之少数最不主要比特被提供。
Abstract in simplified Chinese:本发明系论及D类放大器,以及系特别论及此种放大器之比特反转式积分三角调制器(SDM)具现体。此种放大器系特别纵非排他地适用于一类似hi–fi和个人型音乐放大器等声频设备中。本发明系提供一种具有多重回授回路滤波器结构之比特反转式积分三角调制器(BFSDM)。此种调制器系包括:一耦合至一比特反转器之量化器、一可决定其次一量化器之输出的前瞻量化器、和一可决定是否要改变其比特反转器之输出的控制器。其调制器系包括一在安排上可将来自此调制器之输出端的回授加至其输入之回授回路。此调制器系包括一补偿器,其可调整此调制器之状态,以便就其量化器之输出的比特反转做修正。此可调整其至量化器之输入,使对应于一具有来自一未做比特反转之量化器输出的回授之输入。
Abstract:
This application relates to MEMS devices, especially MEMS capacitive transducers and to processes for forming such MEMS transducer that provide increased robustness and resilience to acoustic shock. The application describes atransducer structure havinga flexible membrane (101) supported between a first volume (109) and a second volume (110). The transducer structure comprises at least one variable vent structure (401) in communication with at least one of said first and second volumes, said variable vent structure comprising at least one moveable portion which is moveable in response to a pressure differential across the moveable portion so as to vary the size of a flow path through the vent structure. The variable vent may be formed through the membrane and the moveable portion may be a part of the membrane, defined by one or more channels, that is deflectable away from the surface of the membrane. The variable vent is preferably closed in the normal range of pressure differentials but opens at high pressure differentials to provide more rapid equalisation of the air volumes above and below the membrane.
Abstract:
A clock generator receives a first input clock signal and a second input clock signal. A first frequency comparator generates a first frequency comparison signal based on a ratio of a frequency of the output clock signal to a frequency of the first input clock signal, and a first subtractor forms a first error signal representing a difference between an input desired frequency ratio and the first frequency comparison signal. A first digital filter receives the first error signal and forms a filtered first error signal. A second frequency comparator generates a second frequency comparison signal based on a ratio of a frequency of the output clock signal to a frequency of the second input clock signal, and a second subtractor forms a second error signal representing a difference between the filtered first error signal and the second frequency comparison signal. A second digital filter receives the second error signal and forms a filtered second error signal. A numerically controlled oscillator receives the filtered second error signal and generates an output clock signal. As a result, the output clock signal has the jitter characteristics of the first input clock signal over a useful range of jitter frequencies and the frequency accuracy of the second input clock signal.
Abstract:
An integrated circuit is used for digital signal routing. The integrated circuit has analog and digital inputs and outputs, including digital interfaces for connection to other integrated circuits. Inputs, including the digital interfaces, act as data sources. Outputs, including the digital interfaces, act as data destinations. The integrated circuit also includes signal processing blocks, which can act as data sources and data destinations. Signal routing is achieved by means of a multiply-accumulate block, which takes data from one or more data source and, after any required scaling, generates output data for a data destination. Data from a data source is buffered for an entire period of a data sample clock so that the multiply-accumulate block can retrieve the data at any point in the period, and output data of the multiply-accumulate block is buffered for an entire period of the data sample clock so that the data destination can retrieve the data at any point in the period. Multiple signal paths can be defined by configuration data supplied to the device, either by a user, or by software. The multiply-accumulate block operates on a time division multiplexed basis, so that multiple signal paths can be processed within one period of the sample clock. Each signal path has a respective sample clock rate, and paths with different sample clock rates can be routed through the multiply-accumulate block on a time division multiplexed basis independently of each other. Thus, speech signals at 8kHz or 16kHz can be processed concurrently with audio data at 44.1kHz or 48kHz.
Abstract:
A bipolar output charge pump circuit (100) is provided having a network of switching paths (110) for selectively connecting an input node (VV) and a reference node (VG) for connection to an input voltage, a first pair of output nodes (VP, VN), two pairs of flying capacitor nodes (CF1A, CF1B; CF2A, CF2B), and a controller for controlling the switching of the network of switching paths. The controller is operable to control the network of switching paths when in use with two flying capacitors (CF1, CF2) connected to the two pairs of flying capacitor nodes, to provide a first mode and a second mode when in use with two flying capacitors connected to the flying capacitor nodes, wherein at least the first mode corresponds to a bipolar output voltage of +/-3VV, +/-VV/5 or +/-VV/6.
Abstract:
The invention relates to the integration of MEMS transducers with electronic circuitry on the same substrate. A method of fabricating and integrated MEMS transducer and circuitry is disclosed which is fully compatible with standard CMOS processing and requires no post processing. The transducer is formed by forming at least one membrane layer, a plurality of back-plate layer sand at least one sacrificial structure such that removal of the sacrificial structure leaves the membrane free to move relative to the fixed back-plate. The method also forms circuit layers on the substrate to form the circuit components and involves sharing layers of material such that at least some of the layers which form the back-plate of the transducer also forms one of the circuit layer sand such layer include at least one metal layer and at least one dielectric layer. The method thus reduces the number of processing steps required compared with sequential fabrication of the circuitry and the transducer. Integrated transducer and electronics devices are also taught.
Abstract:
A regulator circuit (400) comprises an input for receiving an input voltage; an output stage, configured to switch between said input voltage and a reference voltage to generate an output voltage, in dependence on a modulated signal; a controller (600), configured to receive an error signal (VERROR) on a control input and to provide said modulated signal to said output stage;an error amplifier (411), for providing said error signal to said controller (600) in dependence on said output voltage; and presetting circuitry (418), configured to estimate said error signal in dependence on at least said input voltage, and for presetting said control input with said estimated error signal.
Abstract:
A MEMS device comprises a membrane layer and a back-plate layer formed over the membrane layer. The membrane layer comprises an outer portion and an inner portion raised relative to the outer portion and a sidewall for connecting the inner portion and the outer portion. The sidewall is non-orthogonal to the outer portion.
Abstract:
A capacitive transducer circuit comprises a capacitive transducer having first and second electrodes. The first and second electrodes are biased by respective first and second bias voltages. An amplifier is connected to receive a first analogue signal on an input terminal, the first analogue signal being generated by the capacitive transducer, and to generate a second analogue signal on an output terminal. A digital feedback circuit is connected between the output terminal of the amplifier and the input terminal of the amplifier. The digital feedback circuit is configured to provide one of said first or second bias voltages. The output of a voltage source which provides the other bias voltage for the capacitive transducer may be filtered by a low pass filter. The low pass filter may comprise a switched capacitor filter circuit.