Programmable logic device input/output circuit configurable as reference voltage input circuit
    6.
    发明授权
    Programmable logic device input/output circuit configurable as reference voltage input circuit 有权
    可编程逻辑器件输入/输出电路可配置为参考电压输入电路

    公开(公告)号:US06346827B1

    公开(公告)日:2002-02-12

    申请号:US09366937

    申请日:1999-08-04

    IPC分类号: H01L2500

    CPC分类号: G11C5/147 G11C5/066

    摘要: A programmable input/output circuit for a programmable logic device input/output pin can be configured in a standard I/O mode, or in a reference voltage mode. The circuit includes a tristatable, but otherwise standard I/O buffer as well as a reference voltage clamp circuit. In reference voltage mode, the I/O circuit is tristated, and the reference voltage clamp circuit passes a reference voltage from the I/O pin to a reference voltage bus. In standard I/O mode, the I/O buffer is operational. The reference voltage clamp circuit isolates the I/O pin from the reference voltage bus and may include undervoltage and overvoltage protection to prevent disturbance of the reference voltage bus by an out-of-range I/O signal.

    摘要翻译: 可编程逻辑器件输入/输出引脚的可编程输入/输出电路可以在标准I / O模式或参考电压模式下进行配置。 该电路包括可跟踪的标准I / O缓冲器以及参考电压钳位电路。 在参考电压模式下,I / O电路被三态化,参考电压钳位电路将参考电压从I / O引脚传递到参考电压总线。 在标准I / O模式下,I / O缓冲区可以运行。 参考电压钳位电路将I / O引脚与参考电压总线隔离,并可能包括欠压和过压保护,以防止参考电压总线受到超出范围I / O信号的干扰。