公开(公告)号：US20100253562A1

公开(公告)日：2010-10-07

申请号：US12819606

申请日：2010-06-21

申请人： Michiko TOKUMARU ,  Heiji Ikoma

发明人： Michiko TOKUMARU ,  Heiji Ikoma

IPC分类号： H03M1/66

CPC分类号： H03M1/002 ,  H03M1/742

摘要： In a multi-channel current steering DA converter, e.g., a two-channel current steering DA converter, reference current sources Irefa and Irefb that can serve as current mirror sources for current sources Ia and Ib are provided in current source matrices 2a and 2b of the channels, respectively. During an operation, the reference current source Irefa or Irefb that is provided in the current source matrix of a channel that is not powered down is selected and used in accordance with control signals 6a and 6b. Therefore, even when one channel is powered down, the full-scale current of the other channel can be maintained at a constant value, i.e., unchanged.

摘要翻译： 在多通道电流转向DA转换器中，例如双通道电流转向DA转换器，可以用作电流源Ia和Ib的电流镜源的参考电流源Irefa和Irefb在电流源矩阵2a和2b的电流源矩阵2a和2b中 渠道。 在操作期间，根据控制信号6a和6b选择并使用在未断电的信道的电流源矩阵中提供的参考电流源Irefa或Irefb。 因此，即使一个通道断电，另一个通道的满量程电流可以保持在一个恒定的值，即不变。

公开(公告)号：US07764211B2

公开(公告)日：2010-07-27

申请号：US12373213

申请日：2007-03-13

申请人： Michiko Tokumaru ,  Heiji Ikoma

发明人： Michiko Tokumaru ,  Heiji Ikoma

IPC分类号： H03M1/66

CPC分类号： H03M1/002 ,  H03M1/742

摘要： In a multi-channel current steering DA converter, e.g., a two-channel current steering DA converter, reference current sources Irefa and Irefb that can serve as current mirror sources for current sources Ia and Ib are provided in current source matrices 2a and 2b of the channels, respectively. During an operation, the reference current source Irefa or Irefb that is provided in the current source matrix of a channel that is not powered down is selected and used in accordance with control signals 6a and 6b. Therefore, even when one channel is powered down, the full-scale current of the other channel can be maintained at a constant value, i.e., unchanged.

摘要翻译： 在多通道电流转向DA转换器中，例如双通道电流转向DA转换器，可以用作电流源Ia和Ib的电流镜源的参考电流源Irefa和Irefb在电流源矩阵2a和2b的电流源矩阵2a和2b中 渠道。 在操作期间，根据控制信号6a和6b选择并使用在未断电的信道的电流源矩阵中提供的参考电流源Irefa或Irefb。 因此，即使一个通道断电，另一个通道的满量程电流可以保持在一个恒定的值，即不变。

公开(公告)号：US20090208179A1

公开(公告)日：2009-08-20

申请号：US11918363

申请日：2007-01-30

申请人： Heiji Ikoma

发明人： Heiji Ikoma

IPC分类号： H04N9/04

CPC分类号： H03M1/0682 ,  H03M1/747

摘要： In an analog video signal generation circuit, an inverting output terminal NDAOUT4 of a first current-steering differential-output D/A converter DAC4 and an inverting output terminal NDAOUT5 of a second current-steering differential-output D/A converter DAC5 are connected together, and the connection point thereof is connected to a current-to-voltage converter RL6 and to the input terminal of an inverting amplifier AMP. The output terminal of the inverting amplifier AMP is connected with a first video signal output terminal COMPout. This structure uses no adders and thus can reduce the price of video equipment, while using the current-steering differential-output D/A converters DAC4 and DAC5 so that currents consumed by the D/A converters are used effectively. Thus, the avoidance of the use of adders allows the component cost to be reduced, while the effective use of currents consumed in the current-steering D/A converters leads to reduction in power consumption.

摘要翻译： 在模拟视频信号发生电路中，第一电流导向差分输出D / A转换器DAC4的反相输出端子NDAOUT4和第二电流导向差分输出D / A转换器DAC5的反相输出端子NDAOUT5连接在一起 并且其连接点连接到电流 - 电压转换器RL6和反相放大器AMP的输入端子。 反相放大器AMP的输出端与第一视频信号输出端子COMPout连接。 该结构不使用加法器，因此可以降低视频设备的价格，同时使用电流导向差分输出D / A转换器DAC4和DAC5，以便有效地使用D / A转换器消耗的电流。 因此，避免使用加法器允许降低部件成本，而有效使用电流导向D / A转换器中消耗的电流导致功耗降低。

公开(公告)号：US20090045993A1

公开(公告)日：2009-02-19

申请号：US12089699

申请日：2006-03-13

申请人： Michiko Tokumaru ,  Heiji Ikoma

发明人： Michiko Tokumaru ,  Heiji Ikoma

IPC分类号： H03M1/12 ,  H03M1/00

CPC分类号： H03M1/002 ,  H03M1/662 ,  H03M1/745 ,  H03M1/747

摘要： A multi-channel current steering DAC (Digital-to-Analog Converter), for example, a 2-channel current steering DAC, includes a plurality of current sources I1, I2, . . . corresponding to the number of bits of a digital input signal DS in each of channels A, B. Each of the plurality of current sources I1, I2, . . . is formed by two small-current sources (I11, I12), (I21, I22), . . . . In the case where a full-scale current is limited to a small value in any of the channels, one of the two divided current sources is turned off by switches Sa1, Sa2. Accordingly, a full-scale current of each channel can be adjusted with a common bias circuit without degrading the resolution.

摘要翻译： 多通道电流转向DAC（数模转换器），例如2通道电流转向DAC，包括多个电流源I1，I2。 。 。 对应于每个通道A，B中的数字输入信号DS的位数。多个电流源I1，I2，...中的每一个。 。 。 由两个小电流源（I11，I12），（I21，I22）形成。 。 。 。 在任何通道中将满量程电流限制为小值的情况下，两个分压电流源中的一个被开关Sa1，Sa2截止。 因此，可以利用公共偏置电路来调节每个通道的满量程电流，而不会降低分辨率。

公开(公告)号：US07019676B2

公开(公告)日：2006-03-28

申请号：US10864376

申请日：2004-06-10

申请人： Heiji Ikoma ,  Koji Oka

发明人： Heiji Ikoma ,  Koji Oka

IPC分类号： H03M1/66 ,  H03M1/00

CPC分类号： H03M1/108 ,  H03M1/742

摘要： A current output type D/A converter for converting a digital signal into an analog signal comprises a control signal input terminal for receiving a control signal supplied from the outside, and an output load element having a switching mechanism for electrically connecting or disconnecting the output load element to/from an analog output node on the basis of the control signal applied to the control input terminal.

摘要翻译： 用于将数字信号转换为模拟信号的电流输出型D / A转换器包括用于接收从外部提供的控制信号的控制信号输入端子和具有用于电连接或断开输出负载的切换机构的输出负载元件 基于施加到控制输入端子的控制信号，来自/来自模拟输出节点的元件。

公开(公告)号：US06791391B2

公开(公告)日：2004-09-14

申请号：US10193442

申请日：2002-07-10

申请人： Hidetoshi Nishimura ,  Masahiro Gion ,  Heiji Ikoma ,  Naoki Nojiri

发明人： Hidetoshi Nishimura ,  Masahiro Gion ,  Heiji Ikoma ,  Naoki Nojiri

IPC分类号： H03L500

CPC分类号： H03K3/012 ,  H03K3/356113

摘要： In a CMOS level shifting circuit including N-channel transistors that have sources to which a digital signal is supplied, a bias voltage Vref is supplied to gates of the N-channel transistors, and the bias voltage Vref is set to be higher than a high level voltage of the digital signal and lower than a value obtained by adding a threshold voltage of the N-channel transistors to the high level voltage of the digital signal. Thus, a level shifting circuit is provided that is capable of outputting a signal having subjected to stable level conversion, even when a voltage level of a low voltage signal is lowered.

摘要翻译： 在包括具有提供数字信号的源的N沟道晶体管的CMOS电平移动电路中，偏置电压Vref被提供给N沟道晶体管的栅极，偏置电压Vref被设置为高于高电平 数字信号的电平电压低于通过将N沟道晶体管的阈值电压加到数字信号的高电平电平而获得的值。 因此，即使当低电压信号的电压电平降低时，也提供能够输出经过稳定电平转换的信号的电平移位电路。

公开(公告)号：US06492849B2

公开(公告)日：2002-12-10

申请号：US09820842

申请日：2001-03-30

申请人： Heiji Ikoma ,  Yoshitsugu Inagaki ,  Koji Oka

发明人： Heiji Ikoma ,  Yoshitsugu Inagaki ,  Koji Oka

IPC分类号： G05F308

CPC分类号： G11C5/143 ,  G11C5/14

摘要： A monitor circuit for supplying a detection voltage reflecting a supply voltage, a reference voltage generation circuit for generating a high-precision reference voltage not depending upon the supply voltage, and a comparator for comparing the detection voltage with the reference voltage and outputting the result of the comparison are provided and, in addition, a controller is provided which is made up of an auxiliary reference voltage generation circuit for generating a low-precision auxiliary reference voltage with less power dissipation and an auxiliary comparator for comparing the detection voltage with the auxiliary reference voltage. The auxiliary reference voltage is set higher than the reference voltage, and when the detection voltage becomes higher than the auxiliary reference voltage to cause the comparison output of the auxiliary comparator to become active, the reference voltage generation circuit is placed in a power-down state, thereby achieving a reduction in current dissipation.

摘要翻译： 用于提供反映电源电压的检测电压的监视器电路，用于产生不依赖于电源电压的高精度参考电压的参考电压产生电路，以及用于将检测电压与参考电压进行比较的比较器， 提供了比较，并且还提供了一种控制器，其由辅助参考电压产生电路组成，用于产生具有较少功耗的低精度辅助参考电压和用于将检测电压与辅助参考值进行比较的辅助比较器 电压。 辅助基准电压设定为高于参考电压，当检测电压变得高于辅助参考电压以使辅助比较器的比较输出变为有效时，基准电压产生电路处于掉电状态 ，从而实现电流消耗的减小。

公开(公告)号：US20120007668A1

公开(公告)日：2012-01-12

申请号：US13240179

申请日：2011-09-22

申请人： Michiko TOKUMARU ,  Heiji Ikoma ,  Kouji Okamoto

发明人： Michiko TOKUMARU ,  Heiji Ikoma ,  Kouji Okamoto

IPC分类号： H04B1/02

CPC分类号： H03H11/04 ,  H03H17/0223 ,  H03H2017/0247 ,  H04L25/02 ,  H04L27/36 ,  H04L27/38 ,  H04L27/3845

摘要： A filter circuit includes two parallel digital filters, a DAC, and an LPF. The DAC includes two parallel decoders, a parallel-to-serial converter, a switch driver, and a switch. A PLL circuit supplies a reference clock to the DAC. A frequency divider provided in the DAC divides the frequency of the reference clock by two, and supplies the half frequency clock to a parallel processing section (the two decoders and the parallel-to-serial converter) of the DAC and the two digital filters. This makes it easy to secure a timing margin, permitting use in high-speed communication on the order of several GHz.

摘要翻译： 滤波电路包括两个并行数字滤波器，DAC和LPF。 DAC包括两个并行解码器，并行转换器，开关驱动器和开关。 PLL电路为DAC提供参考时钟。 DAC中提供的分频器将参考时钟的频率除以2，并将半频时钟提供给DAC和两个数字滤波器的并行处理部分（两个解码器和并行到串行转换器）。 这样可以很容易地确保定时裕度，从而允许在几GHz数量级的高速通信中使用。

公开(公告)号：US07982644B2

公开(公告)日：2011-07-19

申请号：US12887969

申请日：2010-09-22

申请人： Heiji Ikoma

发明人： Heiji Ikoma

IPC分类号： H03M1/00

CPC分类号： H03M1/687 ,  H03M1/745 ,  H03M1/747

摘要： In a current steering D/A converter, a 1LSB current source 1 and a 2LSB current source 2 are binary code current sources for outputting currents with current values weighted by ½, and a 4LSB current source 3 is one of a large number of current sources designed as thermometer code current source with the same structure. In first circuits A1, A2 and A4 for respectively determining constant current values of the current sources 1 through 3, a plurality of MOS transistors with a channel length L3 and a channel width W3 are cascode-connected to one another with gate terminals thereof shared. In second circuits B1, B2 and B4 respectively used for setting high output impedance of the current sources 1 through 3, a plurality of MOS transistors with a channel length L4 and a channel width W4 are cascode-connected to one another with gate terminals thereof shared. Accordingly, the current characteristics of the current sources can be made more uniform while reducing their circuit areas, resulting in improving the linearity of the D/A conversion characteristic.

摘要翻译： 在电流转向D / A转换器中，1LSB电流源1和2LSB电流源2是用于输出电流值加权1/2的二进制码电流源，4LSB电流源3是大量电流源之一 设计为具有相同结构的温度计代码电流源。 在用于分别确定电流源1至3的恒定电流值的第一电路A1，A2和A4中，具有通道长度L3和沟道宽度W3的多个MOS晶体管在共享其栅极端子之间彼此共源共存。 在分别用于设定电流源1至3的高输出阻抗的第二电路B1，B2和B4中，具有通道长度L4和沟道宽度W4的多个MOS晶体管彼此共源共栅，其栅极端共享 。 因此，可以使电流源的电流特性更均匀，同时减少其电路面积，从而提高D / A转换特性的线性度。

公开(公告)号：US20090174587A1

公开(公告)日：2009-07-09

申请号：US12278367

申请日：2007-10-23

申请人： Tomohiro Ogawa ,  Heiji Ikoma

发明人： Tomohiro Ogawa ,  Heiji Ikoma

IPC分类号： H03M1/74 ,  G05F1/10

CPC分类号： H03K17/302 ,  H03K17/687 ,  H03K2217/0018 ,  H03M1/742

摘要： [Means for Solving the Problem] In a current switch circuit A used for a current steering D/A converter, a current switch basic circuit 1 includes first and second transistors Tr121 and Tr122 included in a differential switch 12. A threshold voltage control circuit 5 has an output terminal Vbout controlling the substrate voltage to be outputted to the substrate terminal of each of the two transistors Tr121 and Tr122 included in the differential switch 12 for controlling the threshold voltage of the two transistors of the differential switch. Accordingly, the present invention improves the decrease in the dynamic range of the current switch basic circuit 1 dependent on the threshold of each of the two transistors in the differential switch 12 and realizes a wider output voltage range without causing deterioration in properties even in a case that the power voltage is reduced in the current switch basic circuit 1.

摘要翻译： 解决问题的手段在用于电流转向D / A转换器的电流开关电路A中，电流开关基本电路1包括差分开关12中包括的第一和第二晶体管Tr121和Tr122。阈值电压控制电路5 具有控制基板电压的输出端子Vbout输出到差分开关12中包括的两个晶体管Tr121和Tr122中的每一个的基板端子，用于控制差分开关的两个晶体管的阈值电压。 因此，本发明根据差分开关12中的两个晶体管的阈值来改善电流开关基本电路1的动态范围的降低，并且实现更宽的输出电压范围而不会导致性能劣化，即使在这种情况下 在电流开关基本电路1中电源电压降低。