Decoupling capacitor placement rules in PCB Design - Cell-by-Cell Formula Trace

Sample Data

This data shows different integrated circuits (ICs) with their recommended decoupling capacitor types, the maximum placement distance from the IC in millimeters, and the expected effectiveness of the decoupling.

Cell	Value
A1	Component
B1	Capacitor Type
C1	Placement Distance (mm)
D1	Effectiveness
A2	IC1
B2	Ceramic 0.1uF
C2	5
D2	High
A3	IC2
B3	Tantalum 10uF
C3	15
D3	Medium
A4	IC3
B4	Ceramic 1uF
C4	7
D4	High
A5	IC4
B5	Electrolytic 100uF
C5	20
D5	Low

Formula Trace

IF(C2<=10, "Place capacitor close for high effectiveness", "Place capacitor further with lower effectiveness")

Step 1: C2 <= 10

Step 2: TRUE

Step 3: IF(TRUE, "Place capacitor close for high effectiveness", "Place capacitor further with lower effectiveness")

Cell Reference Map

    A       B               C       D
1 |Component|Capacitor Type |Distance|Effectiveness
2 |   IC1   |Ceramic 0.1uF  |  5     | High

Arrow: Formula checks cell C2 for distance value.

The formula references cell C2 to decide the capacitor placement rule based on distance.

Result

    A       B               C       D       E
1 |Component|Capacitor Type |Distance|Effectiveness|Placement Rule
2 |   IC1   |Ceramic 0.1uF  |  5     | High       |Place capacitor close for high effectiveness

The result shows the placement rule message for IC1 based on the capacitor distance value.

Sheet Trace Quiz - 3 Questions

What does the formula check to decide the placement rule?

A The component name in cell A2

B The capacitor type in cell B2

C The capacitor placement distance in cell C2

D The effectiveness in cell D2

Key Result

IF(distance <= threshold, "Place capacitor close for high effectiveness", "Place capacitor further with lower effectiveness")