Method and apparatus for analog to digital conversion using an impedance device as an identifier

• US 6,384,755 B1
• Filed: 04/09/1999
• Issued: 05/07/2002
• Est. Priority Date: 04/09/1999
• Status: Expired due to Fees

• Current Assignee: Hewlett-Packard Company (HP Inc.)
• Original Assignee: Hewlett-Packard Company (HP Inc.)
• Inventors: Hayden, Douglas Todd
• Primary Examiner(s): WAMSLEY, PATRICK G
• Application Number:
  US09/289,027
• Time in Patent Office: 1,124 Days
• Field of Search: 341/155, 341/120, 341/118, 340/500, 73/29, 702/106, 710/16
• US Class Current: 341/120
• CPC Class Codes: G06F 12/0669 with decentralised address assignment

Abstract

An analog information storage arrangement includes an impedance device, operatively connected to a module, for providing an impedance value corresponding to encoded information. A decoding device is operatively connected to the impedance means. The decoding device reads the impedance value of the impedance device. The impedance device can be provided as an encoded resistor and reference resistor. The decoding device can include a comparator for comparing the read impedance value to a reference impedance value, which can be a resistance read from the reference resistor of the impedance device. Alternatively, the impedance device can be provided as an encoded capacitor and reference capacitor. The decoding device can include a comparator for comparing the read impedance value to a reference impedance value, which can be a capacitance read from the reference capacitor of the impedance device. The decoding device can be provided as an 8-bit or 24-bit analog-to-digital converter. The encoded information can be selected from a group consisting of serial number, location, hardware revision, and date of manufacture. A method of storing and retrieving analog information in an electronic system including at least one replaceable module is also set forth. The method includes the step of providing, in a module, an electrical component containing an impedance value corresponding to encoded information. Next, the impedance value of the impedance is read and assigning an identification value.

Claims

1. In an electronic system including at least one replaceable module, an analog information storage arrangement comprising the following:

at least one analog electrical identification component installed in a module such that replacement of the module entails replacement of the electrical identification component, the electrical component having an electrically readable property set to a predetermined value corresponding to identification information pertaining to the module, the predetermined value being determined using ratiometric techniques; and

an analog-to-digital converter electrically connected to the at least one analog electrical identification component, the analog-to-digital converter being adapted and constructed to read the electrically readable property as an analog value and produce a digital identifier.

2. A storage arrangement according to claim 1, wherein the electrical identification component comprises a resistor.

3. A storage arrangement according to claim 1, wherein the electrical identification component comprises a capacitors.

4. A storage arrangement according to claim 1, wherein the analog-to-digital converter is adapted to compare the read electrical property to a reference value.

5. In an electronic system including at least one replaceable module, an analog information storage arrangement comprising the following:

impedance means, operatively connected to a module such that replacement of the module entails replacement of the impedance means, for providing an impedance value corresponding to encoded information pertaining to the module, the impedance value being determined using ratiometric techniques; and

decoding means, operatively connected to the impedance means, for reading the impedance value of the impedance means.

6. A storage arrangement according to claim 5, wherein the impedance means comprises at least one resistor.

7. A storage arrangement according to claim 6, wherein the impedance means further comprises an encoded resistor and reference resistor.

8. A storage arrangement according to claim 7, further comprising means for comparing the read impedance value to a reference impedance value.

9. A storage arrangement according to claim 8, wherein the reference impedance value is a resistance read from the reference resistor of the impedance means.

10. A storage arrangement according to claim 5, wherein the impedance means comprises at least one capacitor.

11. A storage arrangement according to claim 10, wherein the impedance means further comprises an encoded capacitor and reference capacitor.

12. A storage arrangement according to claim 11, further comprising means for comparing the read impedance value to a reference impedance value, and wherein the reference impedance value is a capacitance read from the reference capacitor of the impedance means.

13. A storage arrangement according to claim 5, wherein the decoding means comprises an analog-to-digital converter.

14. A storage arrangement according to claim 13, wherein the decoding means comprises an 8-bit analog-to-digital converter.

15. A storage arrangement according to claim 13, wherein the decoding means comprises a 24-bit analog-to-digital converter.

16. A storage arrangement according to claim 5, wherein the encoded information is selected from a group consisting of serial number, location, hardware revision, and date of manufacture.

17. In an electronic system including at least one replaceable module, a method of storing and retrieving analog information, the method comprising the following steps:

providing, in a module, an electrical component containing an impedance value corresponding to encoded information pertaining to the module, the electrical component being mounted in the module such that replacement of the module entails replacement of the electrical component module, the impedance value being determined using ratiometric techniques;

reading the impedance value of the electrical component; and

assigning an identification value to the read impedance value.

18. A method according to claim 17, wherein the step of providing an electrical component comprises providing a resistor, and wherein the impedance value is resistance.

19. A method according to claim 17, wherein the step of providing an electrical component comprises providing a capacitor, and wherein the impedance value is capacitance.

20. A method according to claim 17, wherein the step of assigning an identification value comprises assigning an identification value selected from a group consisting of serial number, location, hardware revision, and date of manufacture.