| US 7,576,571 B2 | ||
| Potential comparator and test apparatus | ||
| Shoji Kojima, Tokyo (Japan) | ||
| Assigned to Advantest Corporation, Tokyo (Japan) | ||
| Filed on Aug. 27, 2007, as Appl. No. 11/845,752. | ||
| Application 11/845752 is a continuation of application No. PCT/JP2006/303994, filed on Mar. 02, 2006. | ||
| Claims priority of application No. 2005-059408 (JP), filed on Mar. 03, 2005. | ||
| Prior Publication US 2008/0218218 A1, Sep. 11, 2008 | ||
| Int. Cl. H03K 5/24 (2006.01) | ||
| U.S. Cl. 327—65 [327/63; 327/68] | 10 Claims |
| 1. A potential comparator that derives a magnitude relation between a potential difference between a first and a second signals
forming a differential signal and a predetermined threshold potential, the potential comparator comprising:
a potential comparing section that derives a magnitude relation between two electric potentials that are objects to be compared;
a first divided-voltage generating section that generates a first divided voltage, which is a divided voltage between a predetermined
first electric potential and an electric potential of the first signal, and outputs the first divided voltage as one of the
objects to be compared in the potential comparing section; and
a second divided-voltage generating section that generates a second divided voltage, which is a divided voltage between i)
a second electric potential determined on the basis of the first electric potential and the predetermined threshold potential
and ii) an electric potential of the second signal, a magnitude relation between the first divided voltage and the second
divided voltage corresponding to a magnitude relation between the potential difference between the first and the second signals
and the predetermined threshold potential, and outputs the second divided voltage as the other of the objects to be compared
in the potential comparing section.
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