Title:
DESIGN OF NOISE MEASURING APPARATUS AND NOISE DETECTION COIL
Document Type and Number:
Japanese Patent JP3481795
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To detect noise while specifying a wiring on a printed board by detecting the differential signal of noise detection separately when a coil, having a predetermined axial length a width in the direction parallel with the wiring, is shifted by a wiring pitch.
SOLUTION: An XYZ stage 31 for shitting a noise detection coil 32 fixed to a coil fixing arm 31a three-dimensionally locates the coil 32, in a predetermined attitude, at a predetermined distance from the wiring of a printed board to be measured. Length and width of the coil 32 to be used are set optimally based on the amplitude and the angular frequency of a noise current, the wiring pitch of the printed board and the characteristics of a signal detection system to be used in order to specify the wiring on the printed board through which a noise flows. More specifically, the coil 32 is connected with a load of predetermined impedance and the power difference is detected from an electromotive force being induced in the coil 32 through a field generated by a noise current flowing through the wiring when the coil 32 is shifted by a pitch of wiring. Finally, a generated noise is analyzed by means of a spectral analyzer 34.
Inventors:
Yoshiyuki Kiyosawa
Application Number:
JP24932996A
Publication Date:
December 22, 2003
Filing Date:
August 30, 1996
Export Citation:
Assignee:
株式会社リコー
International Classes:
G01R33/02; G01R29/08; G01R29/26; (IPC1-7): G01R29/08; G01R29/26; G01R33/02
Domestic Patent References:
| JP4166774A | ||||
| JP7191058A | ||||
| JP4315064A |
Attorney, Agent or Firm:
Chieko Tateno