Do Vref, Rref, and Cref values have any correspondence to V_fixture, R_fixture ,and C_fixture parameters in the [Rising Waveform] and [Falling Waveform] section of the IBIS file? - Do Vref, Rref, and Cref values have any correspondence to V_fixture, R_fixture ,and C_fixture parameters in the [Rising Waveform] and [Falling Waveform] section of the IBIS file? Description The *ref and *fixture parameters are two different things: according to IBIS Specification 4.0, the *ref parameters are the test load that the semiconductor vendor uses when specifying the propagation delay and/or output switching time of the model. At that load, Vmeas is where Tco is valid. These numbers help to facilitate board-level timing simulations; on the other hand, the *fixture parameters describe how the buffer was loaded when generating the waveforms. These numbers are useful in calculating the current during HIGH to LOW or LOW to HIGH transitions. Custom Fields values: ['novalue'] Troubleshooting novalue False ['novalue'] ['novalue'] novalue novalue ['Programmable Logic Devices'] ['novalue'] ['novalue'] ['novalue']