公开(公告)号：US5084667A

公开(公告)日：1992-01-28

申请号：US462311

申请日：1989-12-22

申请人： Joseph Drori ,  William S. Jennings Check ,  William H. Owen, III

发明人： Joseph Drori ,  William S. Jennings Check ,  William H. Owen, III

IPC分类号： G05B19/07 ,  G11C17/14 ,  H03H7/25

CPC分类号： G11C17/14 ,  G05B19/075 ,  H03H7/25 ,  G05B2219/23029 ,  G05B2219/23041

摘要： A variable impedance circuit for use in an external circuit is disclosed. The impedance value is selected by an external circuit. The variable impedance is generated between two terminals which are accessible for connection to external circuitry. The impedance provided between these terminals is determined by a control circuit responsive to electrical signals coupled to the control circuit. An internal register in the control circuit stores a value which specifies the impedance between the two terminals. The stored value is copied into a programmable nonvolatile read-only memory in response to a first predetermined electrical signal. Similarly, the value stored in the read-only memory is selectively copied into the internal control circuit register in response to a second predetermined electrical signal. A number of embodiments of variable impedance elements are disclosed which minimize the number of separate resistors required to achieve the equivalent resolution achievable using a series arrangement of resistors.

摘要翻译： 公开了一种用于外部电路的可变阻抗电路。 阻抗值由外部电路选择。 在可连接外部电路的两个端子之间产生可变阻抗。 这些端子之间提供的阻抗由响应耦合到控制电路的电信号的控制电路决定。 控制电路中的内部寄存器存储指定两个端子之间的阻抗的值。 响应于第一预定电信号将存储的值复制到可编程非易失性只读存储器中。 类似地，响应于第二预定电信号，将存储在只读存储器中的值选择性地复制到内部控制电路寄存器中。 公开了可变阻抗元件的多个实施例，其最小化实现使用电阻器的串联布置可实现的等效分辨率所需的单独电阻器的数量。