Solid electrolytic capacitor module with improved planarity

Patent metadata

Field	Value
Publication number	US-9907176-B2
Application number	US-201615082046-A
Country	US
Kind code	B2
Filing date	Mar 28, 2016
Priority date	Mar 28, 2016
Publication date	Feb 27, 2018
Grant date	Feb 27, 2018

Abstract

A module containing a plurality of active capacitors and a sacrificial capacitor is provided. The active capacitors and sacrificial capacitor are aligned along a horizontal direction so that the side surfaces of their cases are parallel to each other. The particular arrangement of the active capacitors and sacrificial capacitor results in a module configuration where the anode terminations for the active capacitors and an external component of the lead frame for the sacrificial capacitor are coplanar so that the module can be mounted to a circuit board via the anode terminations and the external component of the lead frame in a mechanically and electrically stable manner. Further, the center of gravity of the module in the length and/or width directions can be located at a midpoint of the overall module length and/or width, which enhances the stability of the module when mounted to a circuit board.

First claim

What is claimed is:

1. A solid electrolytic capacitor module having an upper module surface and a lower module surface, the module comprising:
a plurality of active capacitors, each active capacitor comprising a capacitor element and an active capacitor case that encapsulates the capacitor element,
wherein the active capacitor case includes an upper surface adjacent the upper module surface,
a lower surface adjacent the lower module surface, opposing side surfaces, a front surface, and a rear surface;
an anode termination having a first external component contacting and parallel to the lower surface of the active capacitor case;
and a cathode termination having a first external component contacting and parallel to the upper surface of the active capacitor case;
a sacrificial capacitor comprising a sacrificial capacitor case, wherein the sacrificial capacitor case includes an upper surface, a lower surface, opposing side surfaces, a front surface, and a rear surface,
wherein the plurality of active capacitors and the sacrificial capacitor are aligned along a horizontal direction so that the side surfaces of the active capacitor cases and the side surfaces of the sacrificial capacitor case are parallel to each other;
and a conductor, wherein the conductor is positioned along the horizontal direction at the upper module surface so that the conductor is in contact with the first external component of the cathode termination of each of the plurality of active capacitors.

2. The module of claim 1 , wherein the lower surface of the sacrificial capacitor case and the lower surfaces of the active capacitor cases are coplanar.

3. The module of claim 1 , wherein the module has a center of gravity located along a midpoint of an overall length of the module, along a midpoint of an overall width of the module, or both.

4. The module of claim 1 , wherein the sacrificial capacitor further comprises a lead frame.

5. The module of claim 4 , wherein the lead frame includes a first external component and a second external component located at a lower surface of the sacrificial capacitor case, a third external component and a fourth external component located at an upper surface of the case, and an internal component disposed along the length of the sacrificial capacitor case.

6. The module of claim 5 , wherein the first external component contacts and is parallel to the lower surface of the case, the second external component contacts and is parallel to the first side surface of the case, the third external component contacts and is parallel to the upper surface of the case, and the fourth external component contacts and is parallel to the first side surface of the case.

7. The module of claim 5 , wherein the first external component of the lead frame is configured to be mounted to a circuit board.

8. The module of claim 5 , wherein the first external component of the lead frame and the first external component of the anode termination for each of the plurality of active capacitors are generally coplanar.

9. The module of claim 5 , wherein the conductor is connected to the third external component of the lead frame.

10. The module of claim 1 , wherein the first external component of the anode termination is configured to be mounted to a circuit board.

11. The module of claim 1 , wherein the anode termination has a second external component contacting and parallel to the one of the side surfaces of the active capacitor case, and wherein the cathode termination has a second external component contacting and parallel to one of the side surfaces of the active capacitor case.

12. The module of claim 1 , wherein a difference in distance from a horizontal plane between the lower surface of the sacrificial capacitor case and the lower surface of each of the active capacitor cases is less than 0.005 inches (0.127 millimeters).

13. The module of claim 1 , wherein the upper surfaces of the capacitor cases and the upper surface of the sacrificial capacitor case are surrounded by a shell.

14. The module of claim 1 , wherein the capacitor element includes an anode, a dielectric layer overlying the anode, and a cathode overlying the dielectric layer that includes a solid electrolyte.

15. The module of claim 14 , wherein the anode includes tantalum, niobium, or an electrically conductive oxide thereof and wherein the solid electrolyte includes manganese dioxide, a conductive polymer, or a combination thereof.

16. A circuit board comprising:
a substrate that includes a mounting surface, wherein a plurality of conductive members are disposed on the mounting surface; and
the module of claim 1 , wherein the sacrificial capacitor further comprises a lead frame, wherein the lead frame comprises an external component located at a lower surface of the sacrificial capacitor case, wherein the external component contacts and is parallel to the lower surface of the sacrificial capacitor case, further wherein the first external component of each of the anode terminations is connected to one of the plurality of conductive members and the external component of the lead frame is connected to one of the plurality of conductive members.

Assignees

• Avx Corp

Inventors

• Vaillancourt Glenn
• Moulton Ken
• Mccarthy Scott
• Laforge Jason

Classifications

• H05K2201/10015

  Non-printed capacitor · CPC title

• H01G9/048

  characterised by their structure (H01G11/22 takes precedence) · CPC title

• H01G9/15

  Solid electrolytic capacitors (H01G11/00 takes precedence) · CPC title

• H01G9/08

  Housing; Encapsulation · CPC title

• H01G9/07

  Dielectric layers · CPC title