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Method for calibrating and monitoring four-corner chamber voltage rails

IP.com Disclosure Number: IPCOM000029241D
Publication Date: 2004-Jun-18
Document File: 7 page(s) / 171K

Publishing Venue

The IP.com Prior Art Database


Disclosed is a method for calibrating and monitoring motherboard's four-corner chamber voltage rails. Benefits include improved functionality.

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Method for calibrating and monitoring four-corner chamber voltage rails

Disclosed is a method for calibrating and monitoring motherboard’s four-corner chamber voltage rails. Benefits include improved functionality.


      A standard is required for motherboard four-corner chamber voltage calibration. The conventional solution is fully manual, is time intensive, and does not produce repeatable, consistent results.

      Four-corner test is a voltage and temperature margin test on a motherboard. During the test, the chamber varies the voltage level from +6% to -6% against its nominal voltage over a range of temperatures. Conventional four-corner chambers have the limitation of delivering an accurate voltage rail to the motherboard due to the lack of a voltage feedback function. Because of the construction of the chamber, voltage rails from voltage generators are routed through a long wire, switches, and relays before reaching the motherboard power connector. The voltage drops significantly across these components. The voltage level that is being measured at the motherboard is not the same as the configured chamber supply and is not the required voltage margin intended for the four-corner test. Each time before the test starts, a manual calibration is performed. The technician uses a voltmeter to measure the 12V, 5V, and 3.3V rails at the motherboard power connector to verify that the nominal voltage is within the +6% and -6% specification margin level. More often it runs into the situation that needs to set the chamber supplied voltage and check on motherboard side if it meets the specification range back and forth several times.

General description

              The disclosed method is a standard method for testing/calibrating the power rails of four-corner chambers. The results are indicated through the light-emitting diodes (LEDs) of the connector that performs the test/calibration. The disclosed method can be extended to check the motherboard power supply power rails.


              Some implementations of the disclosed structure and method provide one or more of the following advantages:

•             Improved functionality due to providing a standardized four-corner chamber test/calibration process

•             Improved functionality due to providing consistent, repeatable results

•             Improved functionality due to shortening the amount of time a chamber is offline for calibration and testing

•             Improved functionality due to providing a check for motherboard power supply power rails

Detailed description

              The disclosed method includes a calibration connector that checks if the voltage rail delivered to the motherboard is within +/- 2% of its nominal or margin voltage. The connector is inserted between the chamber power supply plug and the motherboard power connector for calibration (see Figure 1). The circuit attached to the connector checks for 12V, 5V, and 3.3V at their nominal voltage...