SBAA515A June   2021  – September 2022 AMC3301 , AMC3301-Q1 , AMC3302 , AMC3302-Q1 , AMC3306M05 , AMC3306M25 , AMC3330 , AMC3330-Q1 , AMC3336 , AMC3336-Q1

 

  1.   Abstract
  2.   Trademarks
  3. 1Introduction
  4. 2Effects of Input Connections on AMC3301 Family Radiated Emissions
  5. 3Attenuating AMC3301 Family Radiated Emissions
    1. 3.1 Ferrite Beads and Common Mode Chokes
    2. 3.2 PCB Schematics and Layout Best Practices for AMC3301 Family
  6. 4Using Multiple AMC3301 Devices
    1. 4.1 Device Orientation
    2. 4.2 PCB Layout Best Practices for Multiple AMC3301
  7. 5Conclusion
  8. 6AMC3301 Family Table
  9. 7Revision History

4.2 PCB Layout Best Practices for Multiple AMC3301

The schematic used in testing is the same as the ferrite section of Figure 4-3. However, layout for stacking the AMC3301’s is shown in Figure 4-3.

GUID-20210601-CA0I-3CCZ-HLW0-JRPXDV6RT5PN-low.jpg Figure 4-3 Recommended Multiple AMC3301 Devices Layout

In general, the same layout principles described in Section 3.2 are followed with a two layer board design.

However, a direct and low inductance path from pin 2 (DCDC_HGND) to pin 8 (HGND) of each device is achieved differently. Instead of a trace, a star connection connects both devices between the top and bottom layers at pins 4 and 5. In addition, a pool of copper is used to connect the DC/DC capacitors to DCDC_HGND on the same layer.

Finally, the LDO_OUT capacitors are scaled up to a 1206 package to allow direct and uninterrupted path for the positive and negative inputs underneath the capacitors.