Impact of Supply Voltage and Operating Point in IC PDN Modeling

The effect of different supply voltages and operating points on the impedance characteristics of an integrated circuit is analyzed in this paper. The approach presented is based on S-parameter measurements of a simple but representative electronic circuit, a 74HC14 hex inverter IC with Schmitt trigger inputs. The impedances change significantly with different operating points and the use of decoupling capacitors, but only slightly with different supply voltages. These measurement results are compared to a simple PDN model to illustrate future requirements for more accurate SPICE-level modeling of an IC’s passive distribution network with respect to the IEC 62433 standard.