公开(公告)号：WO2003021770A1

公开(公告)日：2003-03-13

申请号：PCT/US2002/025905

申请日：2002-08-13

Applicant: MOTOROLA, INC.

Inventor： MIDYA, Pallab ,  ROECKNER, William

IPC: H03F3/217

CPC classification number: H03F3/2173 ,  H03F3/2171 ,  H03F2200/342 ,  H03F2200/345 ,  H03F2200/351

Abstract: A modulated signal is connected to a full bridge switching amplifier (16, 18, 28, 30) and is compensated to remove a predetermined frequency and its odd harmonics. The compensation inverts and delays (26) a signal that is connected to a first half of the full bridge and applies the delayed inverted signal to a second half of the full bridge. By delaying by an odd number of half cycles, the carrier and its odd harmonics are cancelled because the same signal exists on both sides of the full bridge output. When these two same signals are subtracted by the full bridge action, the carrier and odd harmonics are suppressed. Spectral nulls may be provided for various signal applications, not just audio, and when various types of modulation techniques are used, such as PWM and PDM.

Abstract translation: 调制信号连接到全桥开关放大器（16,18,28,30），并被补偿以去除预定频率及其奇次谐波。 补偿反相并延迟（26）连接到全桥的前半部分的信号，并将延迟的反相信号施加到全桥的后半部分。 通过延迟奇数半周期，载波及其奇次谐波被消除，因为在全桥输出的两侧存在相同的信号。 当通过全桥动作减去这两个相同的信号时，载波和奇次谐波被抑制。 可以为各种信号应用（不仅仅是音频）以及当使用各种类型的调制技术（例如PWM和PDM）时提供频谱零点。

公开(公告)号：WO2005104377A2

公开(公告)日：2005-11-03

申请号：PCT/US2005/007848

申请日：2005-03-10

Applicant: MOTOROLA, INC., A CORPORATION OF THE STATE OF DELAWARE ,  MIDYA, Pallab ,  MILLER, Matthew R., ,  RAKERS, Patrick L.,

Inventor： MIDYA, Pallab ,  MILLER, Matthew R., ,  RAKERS, Patrick L.,

IPC: H03M1/12

CPC classification number: H03M3/00

Abstract: A system and method for analog-to-digital conversion using digital pulse width modulation (PWM) is disclosed. The method and system according to the disclosed invention converts an analog input signal to a digital signal in pulse code modulated (PCM) form. The disclosed invention uses a feedback circuit to perform PWM of the analog input signal. The PWM signal is then decimated to obtain the digital signal in PCM form. The system according to the disclosed invention requires lower operating frequency and dissipates lesser power than prior art systems providing the same sampling frequency and resolution. The operation at a lower frequency is achieved by obtaining two samples from every pulse of the PWM signal; the first sample being obtained from the right duty ratio, and the second sample being obtained form the left duty ratio. Further, the disclosed invention has lesser implementation complexity and higher signal-to-noise ratio than prior art.

Abstract translation: 公开了一种使用数字脉宽调制（PWM）进行模数转换的系统和方法。 根据所公开的发明的方法和系统将模拟输入信号转换成脉冲编码调制（PCM）形式的数字信号。 所公开的发明使用反馈电路来执行模拟输入信号的PWM。 然后抽取PWM信号以获得PCM形式的数字信号。 根据所公开的发明的系统需要更低的工作频率并且消耗比提供相同采样频率和分辨率的现有技术系统更小的功率。 通过从PWM信号的每个脉冲获得两个采样来实现较低频率的操作; 从正确的占空比获得第一个样品，并且从左占空比获得第二个样品。 此外，所公开的发明比现有技术具有较小的实现复杂度和更高的信噪比。

公开(公告)号：WO1998034286A1

公开(公告)日：1998-08-06

申请号：PCT/US1997020384

申请日：1997-11-04

Applicant: MOTOROLA INC.

Inventor： MOTOROLA INC. ,  HUANG, Jin ,  MIDYA, Pallab ,  MANCINI, Brian, M.

IPC: H01L41/08

CPC classification number: H01L41/044 ,  H01L41/107

Abstract: A transformer circuit (10) for a piezoelectric transformer (12) having dual inputs which can piezoelectrically interfere with one another to provide adjustable output gain. The transformer circuit (10) provides two pulse-position-modulated input signals (18, 20) which are substantially identical waveforms, but being phase shifted from one another. When the signals (18, 20) constructively interfere maximum gain is achieved. When the two signals (18, 20) destructively interfere minimum gain is achieved. The waveforms may be of any arbitrary type including square, sine, triangle, sawtooth or irregular. Both input signals (18, 20) are at a resonant frequency of the piezoelectric transformer (12) and have a fifty percent duty cycle so as to always provide highest efficiency within the transformer (12). In addition, when the two input signals (18, 20) destructively interfere with each other piezoelectrically, the input impedance of the transformer (12) rises so as to lessen power dissipation within the transformer (12) which subsequently reduces adverse heating effects.

Abstract translation: 一种用于压电变压器（12）的变压器电路（10），具有可以彼此压电干扰以提供可调输出增益的双输入。 变压器电路（10）提供两个脉冲位置调制的输入信号（18,20），它们是基本相同的波形，但彼此相移。 当信号（18,20）构造上干扰最大增益时。 当两个信号（18,20）破坏性地干扰最小增益时。 波形可以是包括正方形，正弦，三角形，锯齿形或不规则的任意类型。 两个输入信号（18,20）处于压电变压器（12）的谐振频率处，并具有百分之五十的占空比，从而始终在变压器（12）内提供最高的效率。 此外，当两个输入信号（18,20）以压电方式相互干涉地干扰时，变压器（12）的输入阻抗上升，以便减小变压器（12）内的功率耗散，从而降低不利的加热效应。