芯片内置测试电路的设计

Design of on-chip built-in test circuit

本文介绍了一个精巧的测试电路,采用1个测试端口,可以实现三种测试功能,既可以作为输入端口向芯片输入信号,也可以作为输出端口观察芯片的输出,还可以作为控制端控制芯片的内部状态,有效降低了芯片的可测性设计成本。

This paper proposes an ingenioustest circuit which employs only one I/O port to achieve 3 objectives.The I/O port can be used as an I-port to apply signals to the chip,it can also be used as an O-port to observe signals from the chip,and it can befurtherused to control an internal flag to implement special control to the chip.The proposed test circuit saved 2 I/O ports thus can reduce the chip cost significantly.