| US 7,469,196 B2 | ||
| Measuring a characteristic of a transfer circuit | ||
| Daisuke Watanabe, Tokyo (Japan); and Toshiyuki Okayasu, Tokyo (Japan) | ||
| Assigned to Advantest Corporation, Tokyo (Japan) | ||
| Filed on Dec. 14, 2005, as Appl. No. 11/300,684. | ||
| Prior Publication US 2007/0131848 A1, Jun. 14, 2007 | ||
| Int. Cl. G06F 15/00 (2006.01); G01D 1/00 (2006.01); G06M 11/04 (2006.01) | ||
| U.S. Cl. 702—127 [356/218; 356/943] | 7 Claims |
| 2. A measuring apparatus that measures a characteristic of a transfer circuit transmitting a signal, the transfer circuit
comprising:
an electrical signal sending section that transmits a sending signal;
a current to light converting section that converts the sending signal into an optical signal;
an optical signal transmitting section that transmits the optical signal;
a photo-electric converting circuit that converts the optical signal into an electrical signal;
a level measuring section that compares the intensity of the electrical signal output from said photo-electric converting
circuit and a predetermined reference level to detect a data value of the electrical signal;
an electrical signal receiving section that detects a data value of the electrical signal; and
a timing controlling section that controls latch timing at which said electrical signal receiving section detects the data
value of the electrical signal, and
the measuring apparatus comprising:
a comparing section that compares the data value of the electrical signal received by said electrical signal receiving section
with a predetermined expected value;
a setting controlling section that sequentially changes the reference level and the latch timing with a predetermined resolution;
and
a result storing section that stores a comparison result by said comparing section for each the reference level and the latch
timing.
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