Decoupling capacitor placement in PCB Design - Dashboard Guide

Dashboard Mode - Decoupling capacitor placement

Goal

Understand how decoupling capacitor placement affects power stability in a PCB design by analyzing capacitor count, placement distance, and resulting voltage noise.

Sample Data

Capacitor ID	Type	Placement Distance (mm)	Capacitance (uF)	Voltage Noise (mV)
C1	MLCC	5	0.1	15
C2	MLCC	10	0.1	25
C3	Tantalum	3	1	10
C4	MLCC	8	0.01	30
C5	Tantalum	2	1	8
C6	MLCC	12	0.1	35

Dashboard Components

• KPI Card: Total Capacitors - Formula: COUNTROWS(Data) = 6
• KPI Card: Average Placement Distance (mm) - Formula: AVERAGE(Data[Placement Distance (mm)]) = 6.67
• KPI Card: Average Voltage Noise (mV) - Formula: AVERAGE(Data[Voltage Noise (mV)]) = 20.5
• Bar Chart: Voltage Noise by Capacitor ID - X-axis: Capacitor ID, Y-axis: Voltage Noise (mV)
• Scatter Plot: Placement Distance vs Voltage Noise - X-axis: Placement Distance (mm), Y-axis: Voltage Noise (mV), Points colored by Capacitor Type
• Table: Capacitor Details - Columns: Capacitor ID, Type, Placement Distance (mm), Capacitance (uF), Voltage Noise (mV)

Dashboard Layout

+----------------------+----------------------+----------------------+  
| Total Capacitors (6)  | Avg Placement Dist.  | Avg Voltage Noise    |  
|                      | (6.67 mm)            | (20.5 mV)            |  
+----------------------+----------------------+----------------------+  
|                                                                      |  
|  Voltage Noise by Capacitor ID (Bar Chart)                           |  
|                                                                      |  
+----------------------+----------------------+----------------------+  
|                                                                      |  
|  Placement Distance vs Voltage Noise (Scatter Plot)                 |  
|                                                                      |  
+----------------------+----------------------+----------------------+  
|                                                                      |  
|  Capacitor Details Table                                            |  
|                                                                      |  
+----------------------------------------------------------------------+  

Interactivity

Adding a filter by Capacitor Type (MLCC or Tantalum) updates all components: KPI cards recalculate totals and averages, charts redraw to show only selected types, and the table filters rows accordingly.

Hovering over points in the scatter plot highlights the corresponding capacitor in the table and bar chart for easy comparison.

Self Check

If you add a filter to show only Tantalum capacitors, which components update and what changes occur?

• KPI Cards update: Total Capacitors = 2, Avg Placement Distance = 2.5 mm, Avg Voltage Noise = 9 mV
• Bar Chart shows only C3 and C5 with voltage noise 10 mV and 8 mV
• Scatter Plot shows only points for C3 and C5
• Table filters to show only rows for C3 and C5

Key Result

Dashboard shows how decoupling capacitor placement distance and type affect voltage noise in PCB design.