Ball grid array current meter with a current sense wire

Patent metadata

Field	Value
Publication number	US-12174240-B2
Application number	US-202218062125-A
Country	US
Kind code	B2
Filing date	Dec 6, 2022
Priority date	Sep 26, 2019
Publication date	Dec 24, 2024
Grant date	Dec 24, 2024

Abstract

Electrical current flow in a ball grid array (BGA) package can be measured by an apparatus including an integrated circuit (IC) electrically connected to the BGA package. Solder balls connect the BGA package to a printed circuit board (PCB) and are arranged to provide a contiguous channel for a current sense wire. A subset of solder balls is electrically connected to supply current from the PCB through the BGA package to the IC. The current sense wire is attached to the upper surface of the PCB, within the contiguous channel, and surrounds the subset of solder balls. An amplifier is electrically connected to the current sense wire ends to amplify a voltage induced on the current sense wire by current flow into the BGA package. A sensing analog-to-digital converter (ADC) is electrically connected to convert a voltage at the output of the amplifier into digital output signals.

First claim

What is claimed is:

1. A method of assembling a ball grid array (BGA) current meter apparatus to measure electrical current flow in a BGA package, the method comprising:
selectively applying a conductive attachment material to a first set of attachment pads located on an upper surface of a printed circuit board (PCB);
selectively placing solder balls onto attachment pads of the first set of attachment pads;
reflowing the solder balls to bond them to the attachment pads of the first set of attachment pads;
attaching a current sense wire to further attachment pads located on an upper surface of the PCB and located in a contiguous channel formed by selective placing and reflow of the solder balls to the first set of attachment pads;
attaching a BGA package to the PCB, the BGA package including an electrically connected integrated circuit (IC), by:
aligning the BGA package with the PCB, the BGA package having a second set of attachment pads, located on a lower surface of the BGA package, positionally corresponding to the first set of attachment pads, the second set of attachment pads including an applied conductive attachment material and;
positioning the BGA package so that the second set of attachment pads is adjacent to corresponding solder balls; and
connecting the conductive attachment material to the second set of attachment pads and to the solder balls to create the BGA current meter apparatus.

2. The method of claim 1 , wherein the current sense wire is fabricated from a metal selected from the group consisting of: aluminum and copper.

3. The method of claim 1 , wherein the current sense wire includes a laminated outer insulating layer selected from the group consisting of: polyimide, polyamide, polyvinyl formal (Formvar), polyurethane, polyester, polyester-polyimide, polyamide-polyimide, amide-imide, polymer and insulating varnish.

4. The method of claim 1 , wherein the BGA package further comprises an additional electrically connected IC.

5. The method of claim 1 , wherein the selectively applying of a conductive attachment material to the first set of attachment pads and the selectively placing of solder balls onto attachment pads of the first set of attachment pads includes using at least one mask for locating the solder balls onto the attachment pads.

6. A method of operating a ball grid array (BGA) current meter apparatus to measure electrical current flow in a BGA package, the method comprising:
monitoring, with a current sense wire, a voltage induced by supply current flowing into a BGA package, the BGA package including at least one integrated circuit (IC);
amplifying, with an amplifier circuit, the monitored voltage to produce an amplified voltage;
converting, with an analog-to-digital converter (ADC), the amplified voltage into a digital value representing the supply current;
transmitting, with the ADC, the digital value to external logic device;
logging, with the external logic device, the digital value and a corresponding time value; and
initiating, with the external logic device, in response to the digital value exceeding a threshold, a corrective action.

7. The method of claim 6 , wherein the current sense wire surrounds a group of solder balls electrically connected to conduct current into the BGA package.

8. The method of claim 6 , wherein the amplifier circuit is an operational amplifier.

9. The method of claim 6 , wherein the external logic device is selected from the group consisting of: a computer system, a processor, a service processor, a test instrument and an external logic IC.

10. The method of claim 6 , further comprising performing analysis on logged digital values and corresponding time values.

11. The method of claim 6 , wherein the corrective action includes reducing power supplied to at least one IC.

Assignees

• IBM

Inventors

• Berge Layne A
• Doyle Matthew
• Schoneck Kyle
• Liang Thomas W
• Walther Matthew A
• Bjorgaard Jason J
• Dangler John R

Classifications

• H10W90/724

  between a chip and a stacked insulating package substrate, interposer or RDL · CPC title

• H10W90/701

  characterised by the relative positions of pads or connectors relative to package parts · CPC title

• H10W90/00

  Package configurations · CPC title

• H10W70/093

  Connecting or disconnecting other interconnections thereto or therefrom, e.g. connecting bond wires or bumps · CPC title

• H10W70/63

  Vias, e.g. via plugs · CPC title