Noise filter characteristic measurement apparatus and measurement method, and noise filter selection apparatus and the selection method used it

摘要

[Abstract] Disclosed is suppression of noise emitted from the electronic device itself is subject to noise and attenuation characteristics of the noise filter to be used for improved resistance to noise from the outside, the actual use of electronic devices accurately measured at the corresponding conditions to the situation, which was the database, to allow a minimum of noise measures in a simple manner. A noise filter characteristic measuring apparatus, the impedance with a variable load 6, and the load 6 noise filter 1 is connected to, the measurement unit 4 to measure the attenuation characteristics of the noise by the noise filter 1, the noise filter 1 A first noise injection part 2 disposed on the front side of the load 6 for a second noise injection part 3 arranged from the noise filter 1 on the front side of the load 6, the first noise injection measurement unit 4 from section 2 through the load 6 and noise filter 1 Leading to and includes a first measurement circuit, and a second measurement circuit from the second noise injection part 3 to the measuring unit 4 through the noise filter 1 and the load 6. The measured attenuation characteristics of the noise filter 1 into a database, and selects an optimum noise filter for each noise target device.