Monitoring signals between two integrated circuit devices within a single package

• US 7,133,798 B1
• Filed: 10/18/2004
• Issued: 11/07/2006
• Est. Priority Date: 10/18/2004
• Status: Active Grant

• Current Assignee: Rambus Inc.
• Original Assignee: Inapac Technology Incorporated (Rambus Inc.)
• Inventors: Ong, Adrian E.
• Primary Examiner(s): Nghiem, Michael
• Assistant Examiner(s): KHUU, HIEN DIEU THI
• Application Number:
  US10/967,749
• Time in Patent Office: 750 Days
• Field of Search: 702/117
• US Class Current: 702/117
• CPC Class Codes: G01R 31/31713 Input or output interfaces for test, e.g. test pins, buffers for scan test G01R31/318572
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48111 the wire connector extending above another semiconductor or solid-state body
• CPC Class Codes: H01L 2224/48137 the bodies being arranged next to each other, e.g. on a common substrate
• CPC Class Codes: H01L 2224/48139 with an intermediate bond, e.g. continuous wire daisy chain
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details

Abstract

In one embodiment, a method is provided for monitoring signals communicated between a first integrated circuit chip and a second integrated circuit chip within a single packaged semiconductor device, wherein at least some external terminals for the packaged semiconductor device are shared by the first and second integrated circuit chips. The method includes the following: receiving signals from the first integrated circuit chip at a plurality of bond pads on the second integrated circuit chip; selecting a portion of the received signals; and outputting the selected portion of the received signals from the single packaged semiconductor device.

Claims

1. A method for monitoring signals communicated between a first integrated circuit chip and a second integrated circuit chip within a single packaged semiconductor device, the method comprising:

receiving signals from the first integrated circuit chip at a plurality of bond pads on the second integrated circuit chip;

selecting a portion of the received signals;

outputting from the second integrated chip the selected portion of the signals received from the first integrated circuit chip to outside the single packaged semiconductor device for monitoring of the signals of the first integrated circuit chip;

wherein the second integrated circuit chip comprises a plurality of monitor buffers connected in a daisy chain arrangement, each monitor buffer being individually selectable and associated with a respective one of the plurality of bond pads on the second integrated circuit chip;

wherein selecting comprises selecting one of the plurality of monitor buffers; and

wherein outputting comprises outputting the signal received at the bond pad associated with the selected monitor buffer at the end of the daisy chain arrangement.

2. The method of claim 1 comprising placing the second integrated circuit chip into a test mode.

3. The method of claim 1 wherein performing testing of the first integrated circuit chip comprises measuring a standby current of the first integrated chip.

4. The method of claim 1 wherein selecting comprises generating a respective select signal.

5. The method of claim 1 wherein selecting comprises loading a respective test code into second integrated circuit chip.

6. The method of claim 5 wherein loading occurs during a cycle for a mode register set (MRS) command.

7. The method of claim 1 wherein one of the first and second integrated circuit chips comprises a logic device and wherein the other of the first and second integrated circuit chips comprises a memory device.

8. A method for monitoring signals communicated between a first integrated circuit chip and a second integrated circuit chip within a single packaged semiconductor device, wherein at least some external terminals for the packaged semiconductor device are shared by the first and second integrated circuit chips, wherein the second integrated circuit chip comprises a plurality of monitor buffers connected in daisy chain arrangement, each monitor buffer being individually selectable and associated with a respective bond pad on the second integrated circuit chip for receiving signals from the first integrated chip, the method comprising:

receiving signals from the first integrated circuit chip at the plurality of bond pads on the second integrated circuit chip;

selecting one of the monitor buffers in the daisy chain arrangement; and

relaying the signal received at the bond pad associated with the selected monitor buffer through some portion of the daisy chain arrangement.

9. The method of claim 8 wherein the second integrated circuit chip is designed for a normal mode of operation and a test mode.

10. The method of claim 9 comprising transitioning the second integrated circuit chip from the normal mode of operation into the test mode.

11. The method of claim 8 comprising outputting the relayed signal at one of the shared external terminals for the packaged semiconductor device.

12. The method of claim 8 wherein selecting comprises loading a respective test code into second integrated circuit chip.

13. The method of claim 12 wherein loading occurs during a cycle for a mode register set (MRS) command.

14. The method of claim 8 wherein one of the first and second integrated circuit chips comprises a logic device and wherein the other of the first and second integrated circuit chips comprises a memory device.

15. A system comprising:

a first integrated circuit chip packaged in a semiconductor device;

a second integrated circuit chip packaged along with the first integrated circuit chip in the same semiconductor device;

wherein the second integrated circuit chip comprises monitoring circuitry for receiving signals sent from the first integrated circuit chip to the second integrated circuit chip, the monitoring circuitry for outputting the received signals to outside the single packaged semiconductor device for monitoring of the signals of the first integrated circuit chip; and

wherein the monitoring circuitry comprises a plurality of monitor buffers connected in daisy chain arrangement, each monitor buffer being individually selectable and connected to a respective bond pad on the second integrated chip for receiving signals from the first integrated chip.

16. The system of claim 15 wherein the second integrated circuit chip comprises a memory device.

17. The system of claim 15 wherein one of the first and second integrated circuit chips comprises a logic device and wherein the other of the first and second integrated circuit chips comprises a memory device.

18. A first integrated circuit chip for packaging along with a second integrated circuit chip in a single packaged semiconductor device, the first integrated circuit chip comprising:

a plurality of bond pads at which signals can be received from the second integrated circuit chip; and

a plurality of monitor buffers connected in a daisy chain arrangement, each monitor buffer being individually selectable and associated with a respective one of the plurality of bond pads, the daisy chain arrangement operable to relay the signal received at the bond pad associated with each monitor buffer through some portion of the daisy chain arrangement.

19. The first integrated circuit chip of claim 18 wherein each monitor buffer is separately selectable.

20. The first integrated circuit chip of claim 18 wherein a respective test code can be loaded into the first integrated circuit chip for selecting each monitor buffer.

21. The first integrated circuit chip of claim 18 each test code can be loaded during a cycle for a mode register set (MRS) command.

22. The first integrated circuit chip of claim 18 wherein at least some external terminals for the single packaged semiconductor device are shared by the first and second integrated circuit chips.