2.6.3 Simulations

The target impedance of the VDDIO1 plane is calculated as 330 mΩ based on the following values (see Power Supply):

  • VSUPPLY = 3.3 V
  • Itrans = 500 mA

  • Ripple = 5%

The following figures show the impedance of the planes (VDDIO1 and VDDIO2). The impedance of the plane is improved by decoupling capacitors and is kept under 0.2 Ω till 100 MHz.

Figure 2-21. Impedance Profile of VDDIO1 Plane Over Frequency Range
Figure 2-22. Impedance Profile of VDDIO2 Plane Over Frequency Range