公开(公告)号：US07205920B2

公开(公告)日：2007-04-17

申请号：US11228114

申请日：2005-09-16

申请人： Paul John Morrow ,  Maria del Mar Chamarro Marti ,  Colin G. Lyden ,  Mike Dominic Keane ,  Robert W. Adams ,  Richard Thomas O'Brien ,  Paschal Thomas Minogue ,  Hans Johan Olaf Mansson ,  Atsushi Matamura ,  Andrew Abo

发明人： Paul John Morrow ,  Maria del Mar Chamarro Marti ,  Colin G. Lyden ,  Mike Dominic Keane ,  Robert W. Adams ,  Richard Thomas O'Brien ,  Paschal Thomas Minogue ,  Hans Johan Olaf Mansson ,  Atsushi Matamura ,  Andrew Abo

IPC分类号： H03M1/66

CPC分类号： H03M3/34 ,  H03M3/502

摘要： A sigma-delta digital-to-analog converter comprises a current digital-to-analog converter (IDAC) stage which generates a current depending on an input digital signal. An output current-to-voltage converter converts the generated signal to a voltage on a continuous-time basis. The amplifier used in the output current-to-voltage converter is chopper-stabilized. The converter can be single bit or multi-bit. The IDAC stage can be implemented with a pair of branches, a first branch comprising a first biasing current source and a second branch comprising a second biasing current source. The biasing current sources can be chopper-stabilized by connecting the bias current sources to the output current-to-voltage converter by a set of switches. The switches connect the biasing current sources to the output current-to-voltage converter in a first configuration and a second, reversed, configuration. This modulates flicker noise contributed by the bias current sources to the chopping frequency. from where it can be removed by filtering downstream of the current-to-voltage converter.

摘要翻译： Σ-Δ数模转换器包括根据输入数字信号产生电流的当前数模转换器（IDAC）级。 输出电流 - 电压转换器将产生的信号连续地转换成电压。 在输出电流 - 电压转换器中使用的放大器是斩波稳定的。 转换器可以是单位或多位。 IDAC级可以用一对分支来实现，第一分支包括第一偏置电流源和包括第二偏置电流源的第二分支。 通过一组开关将偏置电流源连接到输出电流 - 电压转换器，可以对偏置电流源进行斩波稳定。 开关将偏置电流源以第一配置和第二反向配置连接到输出电流 - 电压转换器。 这将调制由偏置电流源提供的闪烁噪声到斩波频率。 从那里可以通过对电流 - 电压转换器的下游进行滤波来去除。

公开(公告)号：US07193545B2

公开(公告)日：2007-03-20

申请号：US11228113

申请日：2005-09-16

申请人： Paul John Morrow ,  Maria del Mar Chamarro Marti ,  Colin G. Lyden ,  Mike Dominic Keane ,  Robert W. Adams ,  Richard Thomas O'Brien ,  Paschal Thomas Minogue ,  Hans Johan Olaf Mansson

发明人： Paul John Morrow ,  Maria del Mar Chamarro Marti ,  Colin G. Lyden ,  Mike Dominic Keane ,  Robert W. Adams ,  Richard Thomas O'Brien ,  Paschal Thomas Minogue ,  Hans Johan Olaf Mansson

IPC分类号： H03M3/00

CPC分类号： H03M3/34 ,  H03M3/332 ,  H03M3/424 ,  H03M3/454

摘要： A multi-bit continuous-time sigma-delta analog-to-digital converter (ADC) has a differential input stage which receives an analog input signal current. A multi-bit feedback current digital-to-analog converter (IDAC) generates a multi-level feedback current depending on a digital feedback signal from a flash ADC. An integrator has a differential input that integrates the difference of the generated current by the multi-bit IDAC and the input signal current on a continuous-time basis. The input stage further comprises a first biasing current source and a second biasing current source which bias the input stage in a mid-scale condition. A first summing node connects to the first differential input line, a first differential input of the integrator and the first output branch. A second summing node connects to the second differential input line, a second differential input of the integrator and the second output branch. A set of chopping switches alternately connect the biasing current sources to the summing nodes in a first configuration and a second, reversed, configuration. The converter receives a modulator clock signal at a frequency FS and the chopping switches can operate at FS or a binary subdivision thereof. The integrator amplifier can also be chopper-stabilized.

摘要翻译： 多位连续时间Σ-Δ模数转换器（ADC）具有接收模拟输入信号电流的差分输入级。 多位反馈电流数模转换器（IDAC）根据闪存ADC的数字反馈信号产生多电平反馈电流。 积分器具有差分输入，其通过多位IDAC产生的电流与输入信号电流的连续时间积分。 输入级还包括第一偏置电流源和在中等尺度条件下偏置输入级的第二偏置电流源。 第一求和节点连接到第一差分输入线，积分器的第一差分输入和第一输出分支。 第二求和节点连接到第二差分输入线，积分器和第二输出分支的第二差分输入。 一组斩波开关将偏置电流源以第一配置和第二反向配置交替地连接到求和节点。 转换器以频率F S S接收调制器时钟信号，并且斩波开关可以在F S或其二进制细分上工作。 积分放大器也可以斩波稳定。