摘要 |
An integrated circuit 2 is provided with one or more monitoring circuits 14, 16, 18, 20 in the form of ring oscillators 22. These ring oscillators 22 include a plurality of tri-state inverters 24, 26, 28 containing a current-limiting transistor 42 operating in a leakage mode. The leakage current through the transistor 42 is dependent upon an operating parameter of the integrated circuit 2 being monitored. Accordingly, the oscillation frequency Fosc of the ring oscillator 22 varies in dependence upon the operating parameter to be measured. |