Capacitor PCB Pad Layout Recommendations

Solder pad design, solder application, and component placement are important elements of the soldering process. Excessive transfer of thermal or mechanical stresses to the MLC can result from oversized solder fillets. Nominal pad designs suitable for the solder reflow process are displayed in the interactive land pattern generator. These guidelines represent a starting point in Printed Circuit Board (PCB) design. For further information on the land pattern design, refer to the standard IPC-SM-782A “Surface Mount Design and Land Pattern Standard” published by the Institute for Interconnecting and Packaging Electronic Circuits (www.ipc.org).

Component Placement Considerations and Pitfalls
Solder pad design, solder application, and accuracy of component placement each must be considered when laying out circuits. This is especially true for RF and microwave circuits where incorrect or asymmetrical deployment of these parameters can lead to serious high frequency performance degradation. Designers beware. IPC-SM-782 is an excellent reference document for optimum soldering of components. However, blindly following this standard can lead to less than optimum high frequency performance and or high voltage issues. If you are not concerned with RF performance or high voltage requirements, Johanson recommends that designers follow this standard (IPC-SM-782). However, for those concerned with RF performance, we recommend a smaller land pattern (solder pad).

Click on the package size on the left hand column, and our recommended land pattern will be displayed on the right.

Surface Mount Capacitors
0201 / R05  



0.015
(0.381)

pad-dimensions-1 image for 0201



0.011
(0.2794)
0.023 (0.5842)
pad-dimensions-2 image for 0201
0.006(0.1524)
 
pad-dimensions-3 image for 0201
0.010
(0.254)
0.010
(0.254)
pad-dimensions-5 image for 0201
0.007 (0.1778)
pad-dimensions-6 image for 0201
0.027 (0.6858)

0.013
(0.3302)
pad-dimensions-4 image for 0201
0402 / R07  



0.028
(0.7112)


0.023
(0.5842)

pad-dimensions-1 image for 0402



0.022
(0.5588)



()
0.040 (1.016) ()
pad-dimensions-2 image for 0402
0.0085(0.2159)()
 
pad-dimensions-3 image for 0402
0.015
(0.3683)0.012
(0.3048)
0.015
(0.3683)0.012
(0.3048)
pad-dimensions-5 image for 0402
0.017 (0.4318)0.019 (0.4827)
pad-dimensions-6 for 0402
0.046 (1.1684)0.043 (1.0922)

0.025
(0.635)
()
pad-dimensions-4 image for 0402
0603 / R14  



0.042
(1.0668)


0.042
(1.0668)

pad-dimensions-1 image for 0603



0.032
(0.8128)



()
0.062 (1.5748) ()
pad-dimensions-2 image for 0603
0.013(0.3302)()
 
pad-dimensions-3 image for 0603
0.023
(0.5842)0.020
(0.508)
0.023
(0.5842)0.020
(0.508)
pad-dimensions-5 image for 0603
0.026 (0.6604)0.024 (0.6096)
pad-dimensions-6 image for 0603
0.072 (1.8288)0.064 (1.6256)

0.035
(0.889)
()
pad-dimensions-4 image for 0603
0805 / R15  



0.070
(1.778)


0.053
(1.3462)

pad-dimensions-1 image for 0805



0.054
(1.3716)



()
0.080 (2.032) ()
pad-dimensions-2 image for 0805
0.016(0.4064)()
 
pad-dimensions-3 image for 0805
0.035
(0.889)0.024
(0.6096)
0.035
(0.889)0.024
(0.6096)
pad-dimensions-5 images for 0805
0.026 (0.6604)0.035 (0.889)
pad-dimensions-6 images for 0805
0.096 (2.4384)0.083 (2.1082)

0.050
(1.27)
()
pad-dimensions-4 image for 0805
1111 / S42  



0.127
(3.2258)

pad-dimensions-1 image for 1111



0.103
(2.6162)
0.120 (3.048)
pad-dimensions-2 image for 1111
0.015(0.381)
 
pad-dimensions-3 image for 1111
0.039
(0.9906)
0.039
(0.9906)
pad-dimensions-5 image for 1111
0.066 (1.6764)
pad-dimensions-6 image for 1111
0.144 (3.6576)

0.102
(2.5908)
pad-dimensions-4 image for 1111
1206 / R18  



0.089
(2.2606)

pad-dimensions-1 image for 1206



0.065
(1.651)
0.128 (3.2512)
pad-dimensions-2 images for 1206
0.016(0.4064)
 
pad-dimensions-3 image for 1206
0.040
(1.016)
0.040
(1.016)
pad-dimensions-5 image for 1206
0.072 (1.8288)
pad-dimensions-6 image for 1206
0.152 (3.8608)

0.050
(1.27)
pad-dimensions-4 image for 1206
1510 / S41  



0.122
(3.0988)

pad-dimensions-1 image for 1210



0.098
(2.4892)
0.125 (3.175)
pad-dimensions-2 images for 1210
0.021(05334)
 
pad-dimensions-3 image for 1210
0.045
(1.143)
0.045
(1.143)
pad-dimensions-5 image for 1210
0.059 (1.4986)
pad-dimensions-6 image for 1210
0.149 (3.7846)

0.065
(1.651)
pad-dimensions-4 image for 1210
1812 / S43  



0.167
(4.2418)

pad-dimensions-1 image for 1812



0.127
(3.2258)
0.185 (4.699)
pad-dimensions-2 image for 1812
0.021(0.5334)
 
pad-dimensions-3 image for 1812
0.061
(1.5494)
0.061
(1.5494)
pad-dimensions-5 image for 1812
0.103 (2.6162)
pad-dimensions-6 image for 1812
0.225 (5.715)

0.115
(2.921)
pad-dimensions-4 image for 1812
1808 / R29  



0.125
(3.175)

pad-dimensions-1 image for 1818



0.085
(2.159)
0.190 (4.826)
pad-dimensions-2 image for 1808
0.0205(0.5207)
 
pad-dimensions-3 image for 1808
0.061
(1.5367)
0.061
(1.5367)
pad-dimensions-5 image for 1808
0.109 (2.7686)
pad-dimensions-6 image for 1808
0.230 (5.842)

0.085
(2.159)
pad-dimensions-4 image for 1808
1825 / S49  



0.290
(7.366)

pad-dimensions-1 image for 1825



0.250
(6.35)
0.180 (4.572)
pad-dimensions-2 image for 1825
0.026(0.6604)
 
pad-dimensions-3 image for 1825
0.066
(1.6764)
0.066
(1.6764)
pad-dimensions-5 image for 1825
0.088 (2.2352)
pad-dimensions-6 image for 1825
0.220 (5.588)

0.140
(3.556)
pad-dimensions-4 image for 1825
2211 / R30  



0.150
(3.81)

pad-dimensions-1 image for 2211



0.110
(2.794)
0.225 (5.715)
pad-dimensions-2 image for 2211
0.0205(0.5207)
 
pad-dimensions-3 image for 2211
0.061
(1.5367)
0.061
(1.5367)
pad-dimensions-5 image for 2211
0.144 (3.6576)
pad-dimensions-6 image for 2211
0.265 (6.731)

0.115
(2.921)
pad-dimensions-4 image for 2211
2220 / S47  



0.247
(6.2738)

pad-dimensions-1 image for 2220



0.207
(5.2578)
0.237 (6.0198)
pad-dimensions-2 image for 2220
0.026(0.6604)
 
pad-dimensions-3 image for 2220
0.066
(1.6764)
0.066
(1.6764)
pad-dimensions-5 image for 2220
0.145 (3.683)
pad-dimensions-6 image for 2220
0.277 (7.0358)

0.150
(3.81)
pad-dimensions-4 image for 2220
2225 / S48  



0.322
(8.1788)

pad-dimensions-1 image for 2225



0.262
(6.6548)
0.230 (5.842)
pad-dimensions-2 image for 2225
0.026(0.6604)
 
pad-dimensions-3 image for 2225
0.086
(2.1844)
0.086
(2.1844)
pad-dimensions-5 image for 2225
0.118 (2.9972)
pad-dimensions-6 image for 2225
0.290 (7.366)

0.160
(4.064)
pad-dimensions-4 image for 2225
3838 / S58  



0.434
(11.0236)

pad-dimensions-1 for 3838



0.374
(9.4996)
0.386 (9.8044)
pad-dimensions-2 for 3838
0.030(0.762)
 
pad-dimensions-3 image for 3838
0.090
(2.286)
0.090
(2.286)
pad-dimensions-5 image for 3838
0.266 (6.7564)
pad-dimensions-6 image for 3838
0.446 (11.3284)

0.170
(4.318)
pad-dimensions-4 image for 3838


RF Performance
For good RF performance, engineers designing PCBs should consider the following recommendations for Johanson Passives:

  • Pad Size
    • Johanson recommends smaller pad size when compared to the IPC standard. This is done to achieve a compromise between the best RF performance and optimum solderability.
    • Large pad sizes like those recommended by the IPC-SM-782 standard will have RF impedance effects (which can be negative)
  • Pad Symmetry
    • Symmetrical land patterns (pads) are recommended to achieve better RF performance and reduce the likelihood of tombstoning
  • Solder Fillet
    • Solder fillet size can shift impedance at microwave frequencies. Johanson recommends smaller size fillets and consistent size fillets. Large wavelengths tend to be more forgiving with excess solder. Fillets at higher frequencies (very small wavelengths) are much more affected by poor soldering methods. Johanson recommends that the solder fillet be at the lower tolerances in order to minimize RF disruption.
    • Controlling the solder fillet to the low side is an effort to minimize negative impedance effects that occur at higher frequencies.
    • o Smaller solder fillets minimizes thermal and physical stresses
Safety Capacitors
Caution for Safety Caps layouts – Layouts should meet the 3mm (0.1182”) or 4mm (0.1575”) minimum creepage distance between pads as required in the UL or TUV specifications. Here the creepage distance is defined by the “C” dimension in the layout above.