High voltage and high power boost converter with co-packaged Schottky diode

• US 7,750,447 B2
• Filed: 06/11/2007
• Issued: 07/06/2010
• Est. Priority Date: 06/11/2007
• Status: Active Grant

• Current Assignee: Alpha & Omega Semiconductor, Ltd.
• Original Assignee: Alpha & Omega Semiconductor, Ltd.
• Inventors: Chang, Allen, Cheng, Wai-Keung Peter
• Primary Examiner(s): Vu; Bao Q
• Assistant Examiner(s): Zhang; Jue
• Application Number:
  US11/761,313
• Publication Number:
  US 20080304306A1
• Time in Patent Office: 1,121 Days
• Field of Search: 257/676, 257/777, 323/222, 323/282
• US Class Current: 257/676
• CPC Class Codes: H01L 2224/32245 the item being metallic
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/49171 Fan-out arrangements
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 25/16 the devices being of types provided for in two or more different main groups of groups H01L27/00 - H01L33/00, or in a single subclass of H10K, H10N, e.g. forming hybrid circuits
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/12032 Schottky diode
• CPC Class Codes: H01L 2924/13091 Metal-Oxide-Semiconductor Field-Effect Transistor [MOSFET]
• CPC Class Codes: H02M 3/155 using semiconductor devices only
• CPC Class Codes: H02M 7/003 Constructional details, e.g. physical layout, assembly, wiring or busbar connections

Abstract

A high voltage and high power boost converter is disclosed. The boost converter includes a boost converter IC and a discrete Schottky diode, both of which are co-packaged on a standard single common die pad.

Claims

1. A boost converter comprising:

a boost converter integrated circuit comprising a controller and an N-type field effect transistor (NFET), wherein the controller and the N-type field effect transistor (NFET) are formed on a common semiconductor chip; and

a vertical discrete Schottky diode having a top anode and a bottom cathode wherein the boost converter integrated circuit and the vertical discrete Schottky diode are co-packaged on a common die pad,

wherein the boost converter integrated circuit is mounted to a first die pad and the vertical discrete Schottky diode is mounted to a second die pad and wherein the first and second die pads are attached to the common die pad.

2. The boost converter of claim 1, wherein the bottom cathode is in electrical contact with the second die pad and wherein the bottom cathode is disposed between the top anode and the second die pad.

3. The boost converter of claim 2 wherein the discrete Schottky diode is attached to the second die pad using a conductive epoxy.

4. The boost converter of claim 1 wherein the top anode is electrically connected to a common package pin between the discrete Schottky diode and the NFET.

5. The boost converter of claim 1, further comprising an inductor electrically to the controller.

6. The boost converter of claim 5, wherein the inductor is electrically connected between the controller and the top anode of the Schottky diode.

7. The boost converter of claim 1, wherein the top anode of the discrete Schottky diode is coupled to a drain of the NFET.

8. The boost converter of claim 1, wherein the boost converter integrated circuit is electrically isolated from the common die pad.

9. The boost converter of claim 8 wherein a substrate of the boost converter integrated circuit is P-type.

10. The boost converter of claim 9 wherein the substrate is electrically connected to a voltage.

11. The boost converter of claim 10 wherein the substrate is electrically isolated from the common die pad.

12. The boost converter of claim 10 wherein the substrate is electrically isolated from the common die pad with a non-conductive epoxy selected to withstand a full output voltage rating of the boost converter.

13. The boost converter of claim 8 wherein a substrate of the boost converter integrated circuit is N-type and electrically connected to an output voltage.